After effects error: asked to create unknown property of type Pseudo and Master properties disabled

[Alien J]

I met a Pseudo warning when I tried to open my file in after effects. After I continuously clicked ok, the file would be opened in the end.  But here was how the problem came out. I found out the master properties I made in layers were all reset as default like screenshot 2.  but it's supposed to like they are all manually set already, just like screenshot 3.  All the work I had done was gone. This happened every time I opened this file.

In the file, I used a dropdown menu, expressions, and essential graphics.  The expression is wroten in opacity selection. 

a = thisComp.layer("Null 1").effect("Tile")("Menu")
if(a==1){100}else{0}

Anyone could help? Is this bug? or Did I make any mistake? Thank you guys so much!

[Mylenium]

Simply sounds like your rather extensive use of the dropdowns is simply confusing AE, even more so since no actual property of the layer itself changes. The whole approach seems less than ideal and is kind of against how it's meant to work. It would probably work better if you used a more conventional approach with actually using time-remapping or individual comp rather than instanciating a single "über-comp" over and over again. Mind you, not saying that this isn't a bug, but to me it seems clear why you are getting these problems.

Mylenium

[Alien J]

Thank you very much!