You said that in the portable version that you can install plugins manually by copying SH3P files at the right place. Where is the right place that you say to manually copy them to?

any 64-bit version does not have to be a portable version of the program
Sorry, I don't understand what you mean. Do ...

I forgot to add this, but any 64-bit version (if there is one besides the Jar executable version) does not have to be a portable version of the program. I a fan of portable versions of programs, but in the absence of a portable version (especially one that is definitely 64-bit & can use plugins), I ...

My OS = Windows 7 home premium 64-bit.

I'm new to using "Sweet home 3d 3.7". I always prefer to use a 64-bit version of a program when one is available (because of the RAM limits of 32-bit programs), but so far, the only 64-bit version of "Sweet home 3d 3.7" that I can find is the Jar executable ...