Ok, so a bit crude but the idea is there:
Place the .reaperOSC in the reaper dir OSC folder
load the touchosc layout into your device
Tested here works fine.
How it works (we can do fine tunning later):
0. Run TouchOSC Bridge and then REAPER
1. load SeqBaby in a track
2. Set Record on that track.
3. Check "monitor input", "record:disable" and set "input MIDI:TouchOSC Bridge" (you might have to enable this in Prefs > MIDI inputs)
4. Select the track. If all is well you will see the above image on your device.
The top buttons (Stop, Play etc) I think are pretty self explanatory but ask away if you want to know something. If I know, remember I'm also walking step by step in the dark here, I'll answer...
You can control the parameters with the sliders and maybe extend their size (maybe the patterns one as it might improve changing pattern) but in the future with a small script or action we can do this more easily (think action to advance FX parameter 1 or something, there must be one, or else it's scriptable)
Squares to the right are C3 - A3 (set to send MIDI through touchOSC bridge) and they will work with Seq Baby as long as you mapping is set to this range). You can alter the notes in TouchOSC editor later if you want and rearrange the layout.
Remember if you move something to page 2 you have to change those items OSC messages and where it says /1/something you have to change it to /2/something.
Same with the Reaper OSC layout. When changing something in the Sid.ReaperOSC file you have to restart REAPER for the changes to take effect.
Any questions, fire away. Hope this helps.