I had been using Uniform Server's most recent release to run a few Drupal sites, and have generally found the package to be brilliant (so well done.)

 

However I recently needed to build one using a lower package, 81, so that I could use Apache 2.2 (related to mod_auth_sspi issues.)

 

Ever since then I have been getting extreme bugs when using Drupal sites on it. Officially it still comfortably meets the specs of Drupal 7, but there seems to be a problem trying to enable any Drupal modules. Anyone have any specific ideas what could be causing the problems?

Not sure. Maybe see if you can look in the log files or turn on debug output. It could be that there is an extension that needs to be turned on or a setting changed. Once you get an error message it should be easy to Google it and get a solution.