We have a very old copy of Install Shield (6.31) and have a lot of script files that we need to use. We have downloaded a trial version of 2013 express, but I can't seem to figure out how to load/use the old rul (and .h files). Can we use them in express or do we have to use one of the professional versions?
The Express edition does not have support for InstallScript (saved in .rul files) or for upgrading projects that were created in the version of InstallShield that you referenced. The Premier or Professional edition would be required for that.