Error: blocks workspace is empty

* I got this Error saying "Error: blocks workspace is empty " and if I want to save blank screen. I said no. When App was built -- I am missing some image, media etc. App size is (aia) 3.8 MB

* I had a back-up file from Sunday, when I loaded that backfile it also gave me the same error and same missing files (files are different  but same error). I am 100% sure that I downloaded this file and afterthat built app from this version without any error?

On Sunday APK size was 5.7 MB and Today it is 5.4 MB. Do anyone know how to resolve this. 

Also right now, last 3 time I built app the sizes are different by ~100-300 KBs, is that normal.

Please help

I have the same problem , the size of the app is less than 5mb. I am missing images, after the build. And the same Error frome time to time ...