I'm sorry but, if you are really convinced to use FSX, at least use the latest version of it, which is FSX:SE.
FSX SP2 has still some rendering bugs left, and nobody is going to fix them. Not that FSX:SE is any different, because that one won't be upgraded anymore but, at least, is based on FSX:X-Pack, which never had these bugs which were specific to FSX-SP2