Update README.md

Installations instructions cause of touch bug added.

README.md

@@ -3,6 +3,27 @@ Personal tweaks and builds of marlin 3d printer firmware repositories.
 
 Source code is here: https://github.com/ThomasToka/MarlinbySynman/tree/bugfix-2.1.x-tweakedbyThomasToka
 
+Update 08.02.2023 10:42 CET:
+
+It seems there is bug when pushing touch display fast at initial z-offset configuration via touch screen.
+I opened a bug with the builder of this wonderfull peace of software.
+https://github.com/synman/Ender-3-S1-Pro-Firmware/issues/20
+
+So my instructions for firmware installations are:
+
+- level your bed with old firmware
+- note your z-offset ex. -1.74mm
+- flash new firmware
+- connect with pronterface and issue
+
+M502 ; factory reset
+M851 Z-1.74 ; set your z-offset
+M500 ; save configuration
+M503 ; check if your z-offset matches
+G28 ; home your printer
+on the touch start autoleveling
+after autoleveling your are ready to print.
+
 Instructions: 
 
 Please do the following two tests: