After importing my package I faced this issue. I deleted migx and after reinstalling Its working for me .
Hi All,
My site was migrated to Revo from Evo with Provisioner.
Just experienced same issue "Cannot re-declare class modTemplateVarInputRenderText".
Based on previous comments I have checked TV's properties and found one to have input type of "mintextarea".
So, if you have this kind of errors check:
1. Permissions on Cache folder;
2. TV's input and output types;