Check the sticky threads at the top, how to make Thief run on modern computers. There is now a user-coded patch, originally 1.19 and now 1.21, that not only solves all the little problems like yours but includes a modified engine that is more reliable. There is a link to 1.19 (maybe later) in those sticky threads. If not, check TTLG, Thief General forum. There is one for T1 and one for T2. The patches are installed on top of a fresh install of T1 or T2. T2 must be patched to 1.18 in advance.
Your problem, by the way, is probably a dual core issue. It can be solved by setting affinity. But why bother? Get the patches. All serious Thief players are using them with no issues.
As for the compilations, unfortunately these people repackage the old games and maybe the installer. They do not fix the many other bugs.
"What we've got here is a failure to communicate", the warden (Strother Martin), Cool Hand Luke