It's not normal you have to run the FSDT Live Update before using the sim. If you have, the only possible explanation is that another add-on has mistakenly set some wrong compatibility flags on the FSX.EXE, which the Live Update recognize and fix them back.
It might not be the add-on itself, sometimes Windows changes compatibility settings automatically, because it sees a program is not fully compliant with Windows UAC rules ( that's not the case for any of our products, which are 100% UAC compliant ), or it might also happens because the sim crashed, so Windows tried to help it run better, by setting some compatibility flags that shouldn't be there.
They are not easy to find, some of them are buried in the registry, that's why we reset the correct value from the FSDT Live Update, since they are not easy to find. But definitely you have a not normal situation.
