You have to make sure you're referencing the correct material in the Shape for your reflection. You need to use Maxis "simple_mirror_reflection" NOT anything with "##0x1C050000!" in front of it. I found that out the hard way myself a few months back.

What exactly do you mean? I don't really understand... do I clone a certain mirror? What do I use "simple_mirror_reflection" for? Sorry...
Thank you!

Quoting myself here. If you have already made a few objects and followed tutorials, you know that you have to reference the material for that subset in the Shape Resource. I think it was Wes that said something to that effect in this thread, too.

I don't know what your subset is called for your reflection but if you look at the gmdc, you'll see what it's called. Then click on Shape in the resource list, usually the Parts tab is opened and there you see the subset's name and the TXMT it's pointing to. SimPE always gives the resources of user made objects the prefix "##0x1C050000!" but that will not work with a mirror. You have to remove whatever SimPE did for that subset and simply type in "simple_mirror_reflection" as the TXMT for the glass (reflection) subset.

Sorry... time has been really short for me lately... I'll try that out in the next few days. Thanks