Hello Creality Community, New, Ender 3 pro user here. Installed the BLtouch and installed the firmware for it. All good to this point. The z axis offset for my unit sits at -3.5mm I can set the Z offset but it will not save however I can through the TUNE menu adjust the Z offset distance to printing height. Strange thing is with the micro SD card is the file structure sometimes becomes corrupt as in the model file is is unreadable. Sometimes the entire Micro SD card is unreadable by Windows and to get it working again I am Using (AOMEI partition assistant). I change the drive letter, then format the card, then change the drive letter back to original which for me is "E". At this point I can re-load model files with no problem but I never know when it will fail again. so this seems to be an ongoing issue. I will be upgrading the Micro SD slot to a full size SD card using an adapter kit to cave wear and tear on the micro SD slot in the printer. Upgrades done so far are: -a metal filament feeder assembly -Tempered Glass printing surface -printed a cute clip in tool holder -BL Touch unit -MicroSD to SD card adapter and printed holder.