Count + 1 variable calculation on Studio

Hi, I’m working on Studio ( not Studio Pro) and I can’t make a basic Count +1 on a variable in a Microflow. The only Expressions are for comparison test but not any + or – options so I can’t make the expression $count+1 Could anyone help?
1 answers

:-( tried it myself and hoped that you had set the data type wrong somewhere….

But I couldn’t achieve it as well in Studio. Certainly possible in Studio Pro. 

After adding the expression in studio Pro and syncing to Studio Studio doesn’t allow me anymore to edit the value