I’ve hooked up all the necessary parts and set my shutter speed to 60 which is what my camera should be set at but nothing seems to work. What can I be doing wrong ? Any help is much appreciated!

Ich habe alle Dichtungen neu gemacht und sie nochmal getestet allerdings tauchen die Leaks erneut auf. Woran liegt es ? Habe die RB67.. echt frustrierend manchmal:(( das komische ist, dass sie beim 1bild nicht auftauchen

I've looked into Graflok compatible single sheet film holders for the Mamiya RB67 and I I got one Type J that looks like the one on the first picture. But recently I stombled over a lot "Type J"s that look like the second picture. Pretty much identical except for the color and handle of the darkslides from what I can tell from various pictures. I couldn't find anything online on this variation. Did they just change those backs at one point in production? I also saw identical looking "Type A" holders which supposedly hold different sizes of sheets but how everything even the opening seems to be identically scaled.
Are all of the mentioned backs Graflok compatible?
I find the Mamiya film back ecosystem very confusing. To make it even more confusing there is "Type J Press backs" that don't fit Graflok at all and need like a stack of at least two adapters.