John
I have had issues with new win 10 install but never about downloading anything. I have many posts in computer forum asking about win 10 and such. I am a retired microsoft tech but really ended my career at Win XP, so quite a while ago. 
I have not had to do anything special to download anything. 
May I ask what service you use, I use Comcast. Also you really need the updates. I just delay the updates so I get to choose when to install.
As to how to save the exe of CWbyBL the path that the steven put in his post is it:
C:\Users\<YourUsername>\AppData\Roaming\bandlab-assistant\Downloads. It is a hidden folder so you have to change the view options to see the appdata folder.
But that will not help you since you can not even download it.

Also John
 
You could re download the bandlab CW app again on your Win 8 pc, copy it to a thumb drive (it's only about 560mb)
When you download it thru bandlab asst you will get to a point where it says it is ready to install-a small dialog box. STOP right there. Go to folder mentioned in thesteven's post and mine above. You will see the cw.exe bandlab asst download folder.
just copy it to the desktop or straight to a thumb drive then just click cancel on the install dialog box.
 
Hope that makes sense.
remember folder is hidden until you change the view to allow hidden folders
 
Bandlab doesn't care where you get the exe from, just thatas long as bandlab asst is connected to the internet when you install it.
 

stratman70
You could re download the bandlab CW app again on your Win 8 pc, copy it to a thumb drive (it's only about 560mb)

 
Funny seeing "Only 560mb" -- My first computer with Cakewalk on it had a whopping 20 MB hard drive... my how things have changed!
 
Sadly, I have no advice for Johnbee58. I can add that while my main system is Windows 7 Pro 64 bit ... I do have CbB working on my Windows 10 tablet as a mobile "Noodling" tool. I don't have the very latest update (build 1809) - the one Microsoft aborted because of issues - but it is reasonably current (build 1803) and this works fine.

It could be that an older version of CbB and BA would work. but that assumes you have access to to them.
Maybe it's best to wait for the next update, or an even later update, and hope that works.  
 
If it were a desktop, I would try cloning the drive on your windows 8.1 computer and putting it in the new one. but that is not possible with a laptop, of course. And Microsoft might not let you do that anyway. Probably would run into authorizing issues. They frequently will let you do things like that if you call them and explain the situation. At least they used to. These days who knows.
 
Is your copy of Windows 8.1 retail or OEM? If retail, you can install it on the laptop and it should authorize. That may solve the problem. Plus, you won't have to fight Windows 10 trying to spy on you, force updates etc.
 
I would keep trying, and keep doing what the knowledgeable folks here are suggesting. At some point it will probably click. If not, use that laptop for linux and get yourself another one and hope for better luck.

There have been a lot of threads with folks having issues installing Bandlab assistant. My opinion is it is a bit buggy. All these threads were resolved with " I don't know what I did, but it finally worked on the 5th try".   

stratman70
Also John
 
You could re download the bandlab CW app again on your Win 8 pc, copy it to a thumb drive (it's only about 560mb)
When you download it thru bandlab asst you will get to a point where it says it is ready to install-a small dialog box. STOP right there. Go to folder mentioned in thesteven's post and mine above. You will see the cw.exe bandlab asst download folder.
just copy it to the desktop or straight to a thumb drive then just click cancel on the install dialog box.
 
Hope that makes sense.
remember folder is hidden until you change the view to allow hidden folders
 
Bandlab doesn't care where you get the exe from, just thatas long as bandlab asst is connected to the internet when you install it.
 

That's what I was planning on doing.  DL the next update on Win 8 PC and transfer it to Win 10.  I know it vanishes after the install so I have to grab it after DL.
 
Thanks
JB

Before any of your reinstallation attempts did you first delete the Bandlab folder:
C:\Users\<YourUsername>\AppData\Roaming\bandlab-assistant ?
 

I give up!  I tried EVERYTHING!  I ran the Windows updates.  I disabled my AV and ran as admin.  I went into the appdata and deleted the old bandlab assistant folders and I downloaded a fresh install of the assistant.  I've never been so disgusted by a piece of software.  The POS still will not download and install it!  I even went into the assistant folder and saw the cakewalk exe file, dragged it out and clicked on it but it said that it was corrupted.  It's impossible.  I just hope I NEVER have to install this on a Windows 10 computer.  My days of music making may be over if this happens on a new one I would buy!!!
 
JUST F*** IT!!

I'll try one more thing.  When the update come out next month I'll cop the cakewalk.exe file off of my Win 8 PC (music dedicated PC) and bring it over to this Win 10 POS and try to install it that way.  But I'm not very hopeful that it will be successful.
 
JB

I misunderstood. Yes that will work. Just remember to be logged in to the BL asst when you install it.