I’ve now succeeded in getting both GIMP (2.9.8) and RT (5.3) installed on an external (flash) memory drive to run in portable fashion. In that, same software on different computers/systems. RT preferences allows the specification of “GIMP Installation Directory”. However, the UI forces one to use a graphical interface that allows a navigable dialogue to be used to select a directory. I’m pretty sure this results in the specification of a full (absolute) path which includes the Windows drive letter. However, because this drive can be mounted with different drive letters, there is no such thing as a valid absolute path. Since both RT and GIMP are installed on the same drive it is very easy to specify a relative path that will always be correct.
Is it possible that this setting can be edited in such a fashion that a relative path rather than an absolute path can be specified?