You cannot create old Guitar Pro projects (for example .gtp files from version 4) in the latest versions of the program, simply because it is not backwards compatible. So there really is no way how you could transform .gpx projects to .gtp files.
Convert Guitar Pro 6 format to Guitar Pro project.
We found one software available in the database for this conversion.
Microsoft Windows software - convert gpx to gtp on Windows
Multi-track editor and music composer for guitars
Convert from gpx file format
|Yes, Guitar Pro supports gpx file conversion as a source file type.||Yes||Yes||gpx editor||Yes||No||No||No|
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.