Hey, I just wanted to make a suggestion based on my experiences with Privateer 1 besides the kickass difficult dogfights.
Number one, privateer is good in the fact that it does not have speed timing issues. It works just fine on my olden K6 266mhz machine and it works at the same speed as my really old 486/66. The only thing I've seen that speeds up the game is when you use a joystick. It boosts the speed about 15% or so (it's quite noticable but makes the action more intense)
Ulli's box seems like a little custom rig so it probably has an EMU10K based sound card (SB Live!, Audigy). Except for Creative sound cards, I've had crappy luck with PCI sound cards.
Also, trusty dusty ISA sound cards have lots of issues with getting IRQ's on new motherboards (P-MMX's and up), but you might get lucky.
If you did the decent thing and got the CD version instead of crappy speechless floppies, it might be handy to copy the speech files to the hard disk to save on memory gobbled up by mscdex (it's faster too). The speech files (priv.tre and rf.tre) take up 154 mb's. Simply copy the files to the privater directory and edit the priv.cfg and rf.cfg so:
=D:priv.tre
becomes
=C:\privater\priv.tre
(or whatever your path might be)
Make sure you edit the rf.cfg using rf.tre instead.
Using CuteMouse cand save memory if you need you mouse and there are mscdex alternatives out there to save even more memory.
Good Luck!