I cloned the "measure of a sim" wooden model and replaced the mesh, but when it comes to the texture SimPE refuses to remember the new details. I've followed tutorials on the process (build -> enter new size -> import texture -> update all sizes -> commit) but whenever I return to it the biggest size is just a small very blocky striped image that doesn't even resemble the texture I added.

Is there a way around this?

Are you using the DDS Utilities? That would be build DTX, open image, build, commit and then save to replace the texture. (Right click on the texture and select Build DTX, use open Image to browse for the new texture and then build to accept.)

Other than that the only time I've had an issue was if I was trying to use the wrong size texture so double check that your texture is a multiple of 8. For example you can't use a 250x250 texture it would have to 256x256.

Built DTX is greyed out for this package, but I wasn't aware of texture images having to be a multiple of 8. The tutorials I've followed never mentioned that. I'll try changing that first, sounds like it could be the cause.

Update, seem to be having to same problem. Does the new size have to follow the pattern of the other sizes? For example this packages texture sizes are doubled, with the last being 256 x 256. Would I need to add a 512 x 512 line next?

You have to use the DDS Utilities in order to replaced the texture with a different size than the original. You said that the build DTX option was greyed out -- I don't know if that means there's something wrong with your installation or if you've never downloaded them to begin with?

If you need the tools you can find a link and install instructions here.

Very odd. I knew I had DDS Utilities as the option isn't greyed out for other packages, but I went to install it anyway and Windows confirmed it was already installed. SimPE is being odd for me today. The layout is very oddly coloured, some text I can't read as the boxes are solid black, and now it doesn't recognise DDS Utilities. I'll start by reinstalling SimPE before anything else.