I believe those are the Project Manager errors. Every time it see .SPR it start looking for .SCX. They can be ignored.
You can get rid of the errors by building .PRG instaed of .SPR but it'll require to change calls to the screens as well.

>
>I have the PRGs/SPRs/MPRs all okay in the project. Now when I compile the project I get the following such 114 errors:
>Program C:\VSO\SW\A09\SPRS\A09PCINV.SPR has the following errors:
> Screen Set ADVPCINV - Undefined
> Screen Set ADVPCIN1 - Undefined
>
>For the following lines of code:
>PROCEDURE _1rz0qsqch
> DO advpcinv.spr
>
>PROCEDURE _1rz0qsqcl
> DO advpcin1.spr
>
>I have tried to compile an exe and it seems to be working well (as you predicted) at this point of code yet the compiler is complaining about screensets
>
>Please advise.