Thanks Markus, I've read now your struggles with RC1 
so I have much more to read before I get what one are supposed to do. 
You give a good advice but I already have TCL 4.0 going on NTFS 
on my Acer D250 Netbook so wanted to test the newest thing. 
But I found this very important text by or from RobertS 
...NTFS support is deprecated starting with 4.2
core.gz is not able to mount cde on NTFS to continue loading. 
However. the cde directory should only reside on iso and not be copied to any hard drive.  
Adding the X/GUI extensions to where your normal TCE directory resides will solve your issue, 
and is the expected location. This way individual updates to the X/GUI will occur as for any regular extension.
I fail to get this part 
"Adding the X/GUI extensions to where your normal TCE directory resides will solve your issue, " 
So typical of me I get the first part. NTFS support is deprecated starting with 4.2
The word deprecated? hm have to look up. 
1. to express earnest disapproval of.
2. to urge reasons against; protest against (a scheme, purpose, etc.).
3. to depreciate; belittle.
So does that mean that it is impossible or just looked down upon? 
That one are on ones own. One should not ask in forum about it 
or
 does it mean that it is impossible? I would love that somebody who know how to do  tell how I get core 
with a desktop going even on NTFS.  
Your "(go for a) stable TC 4.1 to play with and
 learn TC. Next go for NTFS" 
To learn TC is impossible for me I am not on that level. I just want to use it. 
But what you write here "Next go for NTFS " seems to contradict what RobertS told us. 
That it can not boot on NTFS "NTFS support is deprecated starting with 4.2" 
But deprecated maybe means discouraged but do work if one really want to? 
so if you did get it going on frugal install on NTFS then I would love to know the 
menu.lst code