The Vortex import works on .txt (generated by Vortex Tracker 1) or .VT2 (generated by Vortex Tracker 2.5), which is in fact the same format with a different extension.

PT3 files can not be imported directly, but by saving them as .txt (in VT1) or as VT2 (in VT2.5), this works all the same.

The import is raw but works quite well. However, due to some huge difference in how the patterns and instruments are designed, some parts were discarded on purpose:

• The hardware sound are not managed. This is because all the hardware management is done on the instrument level in AT2. I could make a more advanced importer, but in many case, the result would not be satisfactory. So I preferred removed this feature, and the musician can modify the imported song to make it sound right.
• The noise and envelope columns in the patterns are not managed at all, for the same reason.
• The pitch, volume and noise increasing/decreasing in the instruments are managed, by generating lines (up to 64). This is not the natural way AT2 works, but at least simple sounds (such as drums or decaying sounds) are converted correctly. Once again, it is up to the musician to adjust the sounds afterwards if he's not satisfied.