> But how do I setup a separate icon on the desktop to open that one while leaving the existing icon to call the original database?
Just create a new shortcut on the desktop that points to the new .td4 file.
Alternatively, make a copy of the current TP7 shortcut and edit it to put the name of the new database on its commandline.
> I want the new database to mirror all my existing preference settings from the Thumbs.td4 database.
ThumbsPlus has global settings that are stored in thumbs.ini.
Other settings are database-specific and these are stored in .tdo.
You could compare .tdo with .tdo to see what's still different between those two.
> Separate question: Is there a limit to the number of files and folders that the v7 database holds? I currently have 301,000 images files in 3,364 folders.
The only practical limit is that a .TD4 database cannot grow larger than 2 GB in size. See File | Database | Statistics to see how far removed you are from that.
Depending on the thumbnails' dimensions and their type and compression level, you may already be approaching that limit. I so, you can use File | Database | Compact to purge any deleted thumbnail records (that may still be taking up space) from the database. If that doesn't help much, smaller or more heavily (JPG-)compressed thumbnails could help, or catalog your image colection in multiple databases.
