Basic installation of GTP3 on Windows 10 is pretty easy, bear with me a moment, I'm gonna un-install it so that I can then re-install it and get the process noted for you.
 
Are you using an audio interface to get plugged into your computer, or maybe plugging a mixer into the built in line input?
 
How are you hooked up to play back your recordings?
 
So you've been pretty much just making stereo or mono recordings of you jam sessions with just minimal overdubs on only some of the recordings?

OK here goes..
 
1. Insert CD, it probably won't auto run, but if it does, stop it or let it stop on it's own, then exit/close it.

2. Click the folder icon near the start button on the taskbar to open the Windows File Explorer, then once in there, select "This PC" from the list on the left.

3. You should see the Guitar Tracks Pro 3 icon in your optical drive, right click on it and select "Open", after that you should be seeing the contents of the CD, now find the Guitar Tracks Pro folder and double click it to go inside, then double click on the Setup.exe file to begin installation.

4. After entering your name and serial #, the "select components" page should come up, I usually do it like this,
- I de-select "Sample Files", these are some bundle files for use with the tutorials in GTP's help files, it is possible that your windows 10 cannot open the built in help files because they changed the help file format back around windows 7 or 8.
- Click the "Options" button in the Audio FX section, then click on the "Select All" button, now, at this point I de-select the following plugins that I don't want installed,
- SpectraFX, it seems pretty unstable and easily crashes GTP3.
- AmplitubeLE, it would require authorization from IK, and after 14 years since GTPro3 was a new product, that's probably not gonna happen, I don't use it anyway.
- GT:FX Tuner, I don't use it, if I recall correctly, it might have been a little flakey.
When done with these selections click the "OK" button, and then the "Next" button to proceed.

5. I don't install the WMA codec, after 14 years I'm sure it's completely obsolete, "Next"

6. GTPro3 will now install.

7. Choose "NO" to registering VST plugins, then "Next"

8. Install Complete, de-select "Launch Guitar Tracks" and "View read Me", click the "Finish" button
Guitar Tracks should now be installed, you can now close the open file explorer window and remove the Installation CD.

Before running GTP3 for the first time, I would un-install the old VST adaptor program, it doesn't work, I've tried at least 7 or 8 times to get it working, but no luck there.

9. Right click on the Windows start button, up at the top of the pop up menu you should see "Apps and Features", click on that and wait for windows to build the list, then scroll down to "Cakewalk VST Adaptor 4", click on it and choose un-install, when it's finished, close the Windows Settings window.
 
10. Run Guitar Tracks Pro 3, first the wave profiler will run, when it's finished click on "Close", and Guitar Tracks should open.

Strryder - Here is my set-up using GTPro3
- Connect all of my microphones to my PA
- Connect an audio cable from PA(REC OUT) to my PC(Microphone In)
- Connect my Stereo Receiver to my PCs(audio in)
This set-up allows me to record raw audio then play-back using my audio receiver.
I've had no teaching/instruction on the proper way to do this, it's just the logical(in my mind) way to get our Jam audio into the PC/GTPro3 application.
 
I'm sure you guys can teach me a better way ...
 

So to summarize how I understand your setup (assumptions):
 
You are just using the PC like a tape deck, with one stereo input (L/R) to record your entire mix live from the PA mixer.
 
All of your live monitoring is done with the PA, so that you are not using any live VST effects plugins in the PC, or monitoring the tracks via the stereo receiver as you play and record.
 
Your stereo receiver (essentially your audio monitoring system) is only used for playback of the recorded session.
 
Then maybe some overdubs afterwards?
 
Years ago my buddies and I used to do basically the same thing for our weekend jam sessions.  It was always fun to relax afterwards and listen to the playback! 
 
That is the most simple and straightforward way to record a full live mix, but if you ever want to get the instruments isolated to individual tracks to make detailed mixing and editing possible, it will necessarily become more involved with technique and/or equipment expense wise.  That is not really a limitation of the programs you have, as what you have is capable of way more than you are using it for.
 
For that last question, you may want to visit the forum devoted to 'Techniques' and ask away with your recording questions over there.  Plenty of expert folks available to help with answers on that topic!  http://forum.cakewalk.com/Community-f87.aspx

Abacab,
Your assumptions are correct. (quick and dirty recordings but fun to listen to)
And yes, I enjoy recording some overdubs to add additional instruments to the mix.
GTPro3 was very easy to do a simple recording:
Open a new Project - deselect 'Metronome during recording' and 'Accent the first beat' buttons then select the 'R' for record and press the Record button.
I fear Sonar Home Studios not as easy to set up a simple recording. I'm trying to learn how to before our Friday jam session this week and I'm struggling ... :-/
 

I can't get past step 1,
From Cakewalk start screen,
Select 'new project' then you have to select one of the following
(basic-4track-16track-empty track-guitar amps or vocals.cwt)
I guess I need to talk to the folks at
Forums.cakewalk.com/community-f87.asps
Forums are a great tool and I really appreciate your help.
Thanks ...

I managed to record a basic track but I can't seem to get the input volume loud enough.
I adjusted the hwd output db to max and the sound card output to max and it sounded a little louder but the audio track strip is only at 1/3 volume. 
How can I get the volume up?

Redstick
I managed to record a basic track but I can't seem to get the input volume loud enough.
I adjusted the hwd output db to max and the sound card output to max and it sounded a little louder but the audio track strip is only at 1/3 volume. 
How can I get the volume up?

'Help > Getting Started Guide, Tutorial 3, Recording vocals and musical instruments > Getting Ready to Record'
 

At this point, we need to check the input levels to make sure they are sufficient and not distorting.

Perform as you would if you were recording and watch the meter on the track respond to the sounds you produce.

If the meter never even comes close to the maximum, increase the input level. If the meter even occasionally reaches the maximum, decrease the input level.

 
If you are using the Windows audio device, you may need to check the "Recording Devices > Properties > Levels" to make sure that is turned up.

I found it - THANKS

Strryder,
This weekend I will try to load GTPro3 in Compatibility mode.
Keep my fingers crossed ...