I think that it would be useful to see which of these 3 loaded FX is the one whose controls are displayed. Perhaps highlight one of the 5 switches?
Also, can I add that Amp FX to another instrument?
Going back to the "Single Coil STR2 Neck 2" the big [FX] button is clicked to show the 8 controls. Those controls have the same names as the list of 8 macro names. So are they in fact the Macro controls or are those 8 knobs the ones assigned to the Macro controls? If the latter, can the assignments be changed / added (one thing I sorely missed in Sonik Synth 2).
Separate question - where will the Multis (previously known as Combis) be stored? Alongside the instruments (that is, in the sounds library) or in the program installation folder (as for ST2)? The former is infinitely preferable.
You can see the name of the loaded effect above the buttons and you can get much more in detail with the effects in the mixer section. Also, you surely can use the amp (and any other effects) on whichever instrument you like. This part of the GUI indicates that there are 5 insert FX per which can be quite powerful.
The Macros are pre-programmed so they cannot be changed. They don't necessarily refer to just one effect (in fact, they hardly ever do) but they did in the case of the Strat 2 instrument pictured.
All SampleTank 3 objects are stored in the same disk path with separate subfolders for Multis, Instruments, Patterns and Imported Samples.