Cannot Record from imported WAV file

Hi Folks,
I'm trying to do something that should be simple and I just can't get it to work. Here's the scenario:
 
I have a mono wav file of a live show and imported it into Sonar. I added some effects to give it a stereo sound. So far so good...
When I try to write it with the changes (effects) I rewind it to the beginning, arm the tracks and hit the record button. I see the counter increment but hear nothing on the headphones. When I stop the recording and play it back the audio is overwritten with silence up to the point where I stopped the recording. I don't think it makes a difference in I'm using a Tascam US-1800 as the replacement for the internal sound card. Can anyone help me to get this working?
 
Thanks in advance!
Jonny

I couldn't find where to freeze the track but I was able to apply the effects per your instructions. It took a while since the file is almost 2 hrs long but it sounds exactly like it should. I have a copy of the original file in a separate folder so if by chance I want to re-work it I can go back to the original. Thanks so much for your help....Now to go back to Sound Forge to split the file into separate files, 1 per song...
 
Jonny

THambrecht
You can also split to songs in SONAR very easy.
We digitaze tapes and vinyl with SONAR for consumers. Splitting a 2-hour file in SONAR takes about 2 to 4 minutes.
SONAR is the fastest software to restaure and split thousends of tapes and vinyl into songs. We do that since 15 years daily.
 

I'm interested your workflow for splitting long projects into songs.
 
Rocky

Ya, I find a wave editor is custom made to do these chores. You could have actually applied the reverb, eq or any effects your heart desires in any wave editor. Most of them will even share plug ins from Sonar. 
 
I like to break live recordings into 5 song chunks so the rendering doesn't take so long. 
I do a lot of stuff on my Tascam DR40 and then edit it in Wave Lab. It is by far the best tool ( for me ) to work on stereo files. 
Licencing means I can only use Wave lab on my one computer so when I'm somewhere else I am forced to use  either Gold Wave, Wavosuar  or Audacity. Compared to Wave Lab those are clunky. Everything takes more actions to achieve.  I tried Sonar but the saving function, like Audacity, requires an Export so is real slow compared to just editing and hitting save like you do in WL.  Once you've used software that does these things in one mouse click or keystroke, all others seem tedious.