It isn't always better to leave it checked. It depends upon the GPU and the driver. It seems for a lot of users things look better with it unticked. You can play with it and see what happens. The style thing may come back and you'll have to untick it again.

You must use the VrImage to .exr tool found on ASGVis website, then open the .exr in an image editor and resave in the format you want.

Another way to sort the textures out natively is to turn on hidden geometry (view->hidden geometry) then sample the texture on the main face and paint it on to every other face. Probably a lot easier to use the UV plugin for anything with lots of faces though, as painting every face can get a bit boring.

No problem