I don't really know much about Sage, and from what I found online (not much), I couldn't determine how the MS Dialer integration worked, so until I can get an actual copy to look at, I probably wouldn't be able to tell if its possible to use IVM or Express Talk instead.
If it works by executing an MS Dialer executable with command line arguments with the number to dial, you could theoretically replace the executable with another one which acts as a bridge and simply takes the arguments and then executes IVM or Express Talk with the necessary arguments to get it to phone the requested phone number.
For the auto importing contact list idea, unfortunately that wouldn't be possible.
Unfortunately the demo only runs for a set number of days and there is no way to extend the trial (otherwise people would abuse this and avoid ever buying the software 
). I suppose in your case if you want to try it with the new modem, you'll have to try it on a different computer to see if it works well and then purchase the product to use on the original computer.
