Simple enough question - I know that if you do something while regenerating, you cause the regeneration timer to reset or cancel altogether. One of these causes a regeneration cure to stop working: applying another salve, applying another salve to that specific body part, applying another regeneration salve, or applying another regeneration salve to that specific body part.

Can someone please tell me which of these it is?

Applying another regeneration salve to anywhere will reset the timer and start it going again. You can apply other salves whilst the regeneration timer is going, to my knowledge.

Thank you - that is exactly what I wanted to know