an 'Invalid Solid' needs you to open the .map, press F10, find the 'Invalid Solid' error and then click on 'Go To' and then close the dialogue box and press the delete key. Keep repeating this until there are no invalid solids left in your .map.
Afterwards you saved it to .map, open it again and repeat the process until there are none. After this you should be able to compile without problem
NOTE: Only ignore the the 'Has Unused Keyvalues' error.




