Yeah, Win 7 is a real treat, can't believe I waited this long to migrate.
Since there's no graphics or animations for a flame thrower it's not possible, but there is a thermal weapon already added, the RPO-A. As said, no anims but it should be considered as one.
If you make the 3d model for the crosbow I'll gladly add it
And I've been down the pistol/scope issue many times before and always decided against it. 'll let the pictures explain it this time:

The next version of BSM might have some new weapons in it, and some new missions and characters. It'll take a month or so before it'll be ready, enough time to play through this release, I hope