mcmac74:
I use the full version of WinRAR but sometimes 7zip will work "better" (I have had files that caused WinRAR to stop with a detected flaw but 7zip successfully extracted them).
Download 7-Zip from SourceForge.net
It's been a while since I set up Synth1 but I do remember that the contents of the 25000-patch library RAR file is supposed to be extracted to a folder created/called "zipbank" in the "Synth1" folder that is created in your VSTplugins directory (where the Synth1.dll file resides) when Synth1 is installed. The 25000-patch RAR file contains a turd load of RAR and ZIP files. Don't further extract these (~256) RAR/ZIP files. The "zipbank" folder should end up loaded with all of these (~256) RAR/ZIP files for Synth1 to be able to read/access the patches they contain.
There are a number of YouTube videos for Synth1 and Dexed.
To complement these two synths, I would suggest that you keep your eyes peeled for giveaways/specials for Air Music Tech's Xpand!2. It's been given away as a free bonus or sold for as low as $1. It's a decent quality ROMpler for the times when you might say something like "I need a tuba sound." It doesn't have deep synth parameter-tweaking capabilities but it holds it's own with 2500+ presets and a variety of sounds that can be combined in its 4-layer engine---and it's easy to use.
Paj
8^)