show alert duplicate label

[Visor]

Dear friends of the forum, on the sheet to show doubled I could do, but on a userform Mostra not find how to do it, especially as showing where warning label shows yellow with red letters the name who doubles. how to achieve this?
Thanks for your help
Upload a sample file

 

[Visor]

For example, the progress that has been possible so far to identify duplicates with VBA and show the warning label, upload it for you to see and I can understand that seeking collaboration regarding operate the rest I climbed in the first post.

 

[Visor]

I put more progress to make me understand better

 

[Visor]

I've done a lot more understandable using logroastur advance, with a long code but is increasingly understood the operation, I upload the file to be seen but there are results still do not want to work well.
I hope some expert throw me a hand with this file that I'm up here
if there is a question if clarification is needed please tell me

 

[Visor]

I think I'll post the item again, to refresh, it seems at this level already lost some interest and I feel that I am acting alone.
Many come take the model, but at least give me your comments, but that obviously is not mandatory.
Please estimated moderator could close the topic?