The toolrack has two main windows: the stomps window, and the amps. The stomps window has 6 stomp slots with an extra slot reserved for the amp. This is so you can move the amp from left to right so you can have stomps before and after it. So if you're using the toolrack plugin, the maximum number of stomps you're going to have at any one time is 6. So when you look in the parameters list and you see slot 1 control 1, that's the first slot. If it had a distortion pedal in there, control 1 would refer to the first control of the distortion pedal. I don't know how you'd determine which pedal is in which slot using NVDA and reaper. There is a dropdown menu beneath each slot that has all the stomps listed, so if you have sighted assistance, you could do golden cursor points to click them to enter that stomp into the slot. If the slot already has a stomp in it, the name of that stomp will be greyed out and say unavailable because it's already in the slot. So you could use this information to determine which effect if any was in the slot. On the amps window, there are two amps side by side, left and right. You can click a button that links the two, so that whatever you change on the left, it also changes the one on the right. This means that it sounds like a single amp. But if the one on the left has different settings to the one on the right, it'll sound like a split, so it sounds like you're playing two guitars at once. To be honest, I tend not to tinker too much with the amps. I just accept the preset, and make little tweeks to the stomps, particularly the delay because it has to match the tempo.
Here is a list of the 26 stomp FX in alphabetical order as they appear in the menu. I'll also write out what controls they have. Each stomp also has a bypass toggle switch.
1. Axpress
Control 1 press. Control 2 attack. Control 3 output.
2. Buzz.
Control 1 drive. control 2 level. control 3 tone.
3. Chorus.
control 1 depth. control 2 rate.
4. Compression.
control 1 comp. control 2 attack. control 3 release
5. delay.
control 1 mix. control2 time. control 3 hi cut. control 4 feedback. control 5 stereo. control 6 sync. Note, sync is a toggle that syncs to the tempo of the daw.
6. Distortion
control 1 drive. control 2 level. control 3 contour. control 4 tone.
7. Doubler
control 1mix. control2 detune. control 3 delay. control 4 feedback. control 5 stereo.
8. EQ
control 1 125hz. control 2 250hz. control 3 500hz. control 4 1Khz. control 5 2Khz. control 6 4Khz.
9. flanger
control 1 mix. control 2 rate. control 3 delay. control 4 feedback. control 5. stereo. control 6 sync.
10. fuzz
control 1 sustain control 2 level. control 3 tone.
11. gate.
control 1 threshold. control 2 hold. control 3 attack. control 4 release.
12. gatecomp
control 1 gate. control 2 comp.
13 LayD
control 1 mix. control 2 time. control 3 pitch. control 4 stereo. control 5 feedback. control 6 sync. control 7 reverse. note, reverse is a on off toggle.
14. metal
control 1 dist. control 2 level. control 3 hi. control 4 low. control 5 frequency. control 6 gain.
15. octaver
control 1 oct 1. control 2 oct 2. control 3 pan 1. control 4 pan 2. control 5 direct.
16. overdrive.
control 1 drive. control 2 level. control 3 tone.
17. panner
control 1 rate. control 2 width. control 3 sync. control 4 sine. note, sine is a 5-way switch that chooses different waves such as sine, square triangle etc.
18. phaser
control 1 depth. control 2 rate. control 3 stereo. control 4 sync.
19. pitcher bass
control 1 mix. control 2 min. control 3 max. control 4 pitch. note, pitch is a slider that controls the amount of pitch shift.
20. pitcher
controls are same as pitcher bass.
21. reverb
control 1 mix. control 2 time. control 3 predelay. control 4 tone.
22. spring reverb
control 1 mix. control 2 predelay. control 3 time.
23. tone
control 1 low. control 2 mid. control 3 high. control 4 low cut. control 5 high cut.
24. vibrolo
control 1 vibe. control 2 trem. control 3 rate. control 4 sync. control 5 sine.
25. volume
control 1 min. control 2 max. control 3 lin. control 4 volume. note, volume is a slider.
26. wahwah.
control 1 sensitivity. control 2 range. control 3 speed. control 4 auto, this is an on off toggle. control 5 slider, don't know if this doesn't have a name or if I just called it slider.