Hi, yesterday I read your question, upon searching the web. One and a half year old, your question might have been answered already. Still someone might be interested. I am using the digital Leica M9 body on the Reprovit II in the archive here. This works fine. I operate the shutter with a bulb release. A long wire release should do it also. The camera is connected by an USB cable to the computer (Linux). The release can only be triggered, as long as the cable is not connected to the PC. As soon, as it ist connected, the SD card in the body can be accessed, as if it where put into the slot of the notebook, or like accessing any other USB device.
There is some mechanical work to be done: The male bayonet mount which is attached to the camera-slide of the Reprovit does not have the notch, where the sprin-loadad peg in the female camera-bayonet fits in. In earlier times the Leica M bodies had a small peg at the left side near to the bottom (under the rewinding knob / crank. This fits into a spring-loaded lever which is attached to the slide, whose purppose is, to keep the camera parallel to the slide, when it is attached to the not-locking bayonet mount. All the later M-bodies dont have that "Reprovit-peg" any more. A simple way of fixating the body is, to put a wooden ruler, a few mm thick, in between the bottom cover of the body and the edge of the slide, which should keep the body straight, if it has just the necessary thickness. What I did is: I took a Leica standard male lens-bayonet, which I once bought at a photo fair, which has the slot for the locking-peg of the camera, and replaced with this the original Reprovit bayonet mount. It is no problem to push the lens-release button on the camera in order to take off the camera from the Focoslide.
More of a problem is the connection of the USB-cable, with the body attached to the slide: The small USB-connector must have a 90° angle; still I had to remove some of the plastic from the connector. And I had to remove the aforementioned spring loaded lever from the Focoslide. Two scews hold it in place. Those and the lever fit into a 35mm Film container, to safeguard them.
With the Reprovit, the M9 and a Linhof book cradle I can digitize paper-files in the archive much faster, than with the flatbed-scanner. And with tesseract I get good OCR of printed, and typewriter text. The only problem is, that the camera has to be nearly upmost on the Reprovit, which yields just 250 dpi resolution. For the open source software tesseract 300 dpi are recommended. Two years ago a second hand M9 did cost approximately half of the original price. Now with the M10 on the market, the M9 should be cheaper. If anybody knows about a digital body which has quite higher resolution than 18.1 MP and which can be adapted to M-lenses, I would like to learn about that. Have fun!