To play on Vassal, I see the module and extensions. I don't see the Scenarios - and the Avalanche website only seems to sell the boxed set. Is there a purchasable PDF or similar of the book/scenarios available that I am not seeing on their website? Or is there an alternate source ? Thanks.
Unless you can find something on eBay or the 2nd-hand sites, the functional answer is no.
One of the conditions for allowing Vassal support in the PG-verse, and for avoiding C&D letters to PG-HQ, is that scenarios are not to be published on the site or shared in the forums. APL holds the copyright, so them's the rules.
Someone in Canada on BGG put one up for sale 2 years ago at $45. Worth contacting them to see if they still have it. Shipping will be much cheaper and you might be able to talk them down a bit:
