HiRise is Mars data, but not *MOLA* data. MOLA is a specific instrument. Just so that's clear, in case you get any other confusion from mixing those terms. When dealing with GIS data it's good to be as specific as possible because there are so many data and file types and variations.
Creating a seamless wrap on a planet *with a single file*, especially a non-georeferenced one (i.e. manually-created rather than real-world sampled), is quite different than dealing with a real-world tiled data set with georeferencing. But I do understand why you might have thought it was a more related question.
In any case, my first question would be whether you have tried loading the data directly in TG. If so, what problems are you seeing? Keep in mind that HiRise data is *not* planet-wide and contiguous for Mars. It's quite patchy actually.
- Oshyan