Interesting that you are the only one who still try to setup him,
I wondering that you ( like you write) try so many things but never get in touch with the original grr forum.

Also wondering that hundrets of that set were sold and from the most they never hered anything so sound like all running

I will not say the printer is perfekt but for a Printer who is already more than 10 years old he is still useable today ( there are only a few update over the years like dd3 / alluminium parts ..)

you buy a DIY but not get it working , but reworked by yourself a lot like it looks like less knowing about it ( sorry why should someone try to use a nema 23 for Z if its already soo much force necessary to move it)

the english manual could be better sure like all buildup desriptions , but also the english one had all information to build it up so long enough ground knowings are exiting.

that your tickets not answared like you want I wondering the only point i would belive someone was not able to build it up and want to get every single step done by them and after destroying parts to get them recovered

and if there was someone wrong they normaly try to do her best ( one case they send parts to a 500€ printer to the USA bec a board was defect the cost were extream but they did .

what show me that your knowledge for 3d printers is less is also:

You write about the washers , sure can be all special parts, but this parts cost a lot and no one want to pay that at that time

te x400 was for that time a great big printer for a great price

you can also buy a compleate one for much more ( the lot work for assambly need to be paid its not a serias production)

so my proposal sell it for an extream cheap price ( for me it sound you destroy a lot of the parts) or give him to a few student for learning

Compare to other companies GRR have a support tieckt system ( the most dont have or ever answare) and the products working ( so long with the right skill mounted or ready bought)

I have an X400 an NEO and Protos , our Makerlab has an NEo an X350 2 Ultis and a few other the only ones who are save that working a normaly the GRR ones

so far to that