You know, all the problems I've had with the game have been the same in 98 as they were in 98 and Dos 5.0.
Crashing in X-Com UFO and TFTD has been a way of life ever since the game hit the market. Crashes happen.
Some players are very lucky and they never happen at all, and others are very unlucky. Then there are those that cannot even get the game to run no matter what.
There are so many causes for some of the crashes that it's hard for us to just hand you the silver bullet and make everything right. Before it was 'Get the latest patches'. Then we moved on to 'Get moslo or some other slowdown utility'. These days it's 'get DosBox' or 'Get the Collectors Edition and the graphic patches', etc. While these work great for most compatibility and speed issues, it doesn't stop all the causes for the various crashes that have been in the game since the beginning. Like the crashes that occur when you step out of the Skyranger, or the game just crashing in the middle of a battle for no apparent reason. These can happen in any of the games.
So, save often and be very patient with the game.
Saving, quitting the program and then restarting it from to time to time is also good pratice if you've been playing for a while.
NKF, narrow minded fuddy duddy who refuses to let go of the past and will not accept anything newer than 1979.