[stumped]

i am getting closer to a workable solution ( for a number pad entry gizmo)
i discover tht PDFxchange will open files into to multiple tabs within one instance
then CTRL-TAB is its shortcut for next tab. With powertoys I can assign that to an unused key on the data pad e.g. to / , and assign F11 for full screen to key *

so my wired pad ( when it arrives ) should give me all of next, previous page, full page toggle, and next tab...

also experimenting with exporting all my music pdf via calibre's save to disc so that all music is in a single flat folder, where its easy to open multiple files in windows

i am a bit stuck behind windows inability to show useful " covers" for pdf files, like caibre can.

i mostly play short things, but I am also using some thick books e.g. fake books, where its easier to export the page(s) i want with print to pdf rather than have to get to page 283 or whatever.... and not have to remember which fake book has the best version of which song...

i could then merge the fake book leadsheets I actually like into one slim volume I guess, discarding several hundred pages that are not of interest.

i read somewhere that another approach is to make version of song file with extra duplicate pages inserted for musical repeats, so that you never need to go backwards. nice idea, tedious to have to implement... and many repeats do not go back to a start of page position

[ about 20 years ago I bought a big indexed set of fake book pdfs from someone on ebay - i still have them, though several are poor quality for legibility from a distance. . The new real book series are the best typeset / most legible ]

i also recently bought a couple of steely dan transcriptions ( all keyboard, voice, & guitar parts) from a web site playlikethegreats.com. those are excellent, but delivered as a set of PDFs one for each instrument. he only had those 2 songs by SD though . & I found some accurate bass [notation] transcriptions for other Steely Dan on specialist bass guitar sites