As seen on ReprapFirmware thread, I started using RRF in my Dollo rework. After some tuning it seems to be working quite nicely. Time will tell if it's going to be my main driver. Luckily switching back and forth between Marlin and RRF is easy, just copy the firmware.bin to sdcard and boot the board. When going from RRF to Marlin, mesh bed leveling needs to be redone though as EEPROM is lost in RRF flash. Such problems don't exist with RRF as all configuration is in files on sdcard.
Tuning the RRF exposed a problem on the printer, though. The part cooling is inadequate so redesing is needed, along with changing the 40mm axial fan to radial if possible. Mor on that later.

I added a Z-motor support for both of my Dollo's. The design is quite simple, the leg just clips on to the Z-motor. The leg is adjustable. It does seem to help, at least on the Dollo rework, mesh bed leveling seems to have much better resolution now. So apparently the beam supporting the Z-stuff was having some slack after all. Haven't tested this on Dollo.2 yet, just finished installing the parts.
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