Well, I don't really know what the problem is.
First of all I should say that I think all the Basic versions that come with Zipped versions must be my programs.
Secondly, I believe that I compiled these Basic programs to produce the Zipped versions.
So what is different? Well maybe you are right, that all your hardware additions and improvements are causing Zzzip to have problems.
As far as I can remember, the error message "Too many Labels" means that the Assembly Language file (created during passes 1 and 2) is using too much memory for labels (at this moment I can not remember exactly what the limit is or even why there has to be a limit). Most of the labels are used for Basic line numbers, so reducing the number of lines would obviously help. I don't have my Enterprise set up and working at the moment (and I really should not spend time playing with it when I have to get ready for my holiday). But in April I will try compiling these programs on my computer and see if I get any problems.
I am also puzzled by the comment from szipucsu that Tetris does not work. It works on my machine without any problems. However the next post from Zozo might explain this. As far as I can remember, compiled programs will only work if there is a Basic ROM cartridge present - and of course in the days when Zzzip was written, there was only one Basic ROM - the English one. If that is correct, it would not be surprising that they did not always work when a different Basic ROM cartridge was present - in fact it would be surprising if they ever worked. I guess that the full explanation might be that the compiled program only uses the Basic ROM for certain functions, and therefore it would work sometimes but not in all cases. For example I am beginning to remember that Single Dimension Arrays were given special treatment by Zzzip, so that they would run faster - this meant that Zzzip created completely independent code in the compiled program to handle these arrays. However arrays with more than one dimension were handled by calling the appropriate subroutine in the Basic ROM - so they were not speeded up as much, but the benefit was that I avoided a large increase in the size of the compiled program. I expect there were some other functions that were treated in the same way.