Using .vit for multiple instance

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Hi,
 
I have a main vi, uses rendevous to run multiple subvis at the same time, that needs to be opened separately per user which need to open the same vi multiple times.
I tried to use .vit, changed main vi to vit. Created new vi that calls this main.vit. However this doesn’t run multiple times, only opens the first window. Then I used subVIs as vit. This even creates a bigger problem. The sub vi’s that opened doesn’t run.
 
I think I’m missing some basic concepts of using vit. I searched the forum, found some articles but I can’t find what I’m doing wrong.
 
Should main vit calling several sub vit’s work?
 
Any tips, comments would help.
 
Thank you very much.