Sorry, I'm afraid you've moved beyond my ability to diagnose. This is your code exactly as posted, and the second run with the number of threads increased to 10, but otherwise unchanged: 

c:\test>perl1
Starting LetsRock()
WaitForThreads() started
waiting for 1
Use of uninitialized value in print at perl_module1.pm line 43.
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 2
waiting for 3
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 4
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 5
Use of uninitialized value in print at perl_module1.pm line 43.
WaitForThreads() finished
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
LetsRock() ended

c:\test>perl1
Starting LetsRock()
WaitForThreads() started
waiting for 1
Use of uninitialized value in print at perl_module1.pm line 43.
Use of uninitialized value in print at perl_module1.pm line 43.
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 2
waiting for 3
waiting for 4
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 5
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 6
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 7
Use of uninitialized value in print at perl_module1.pm line 43.
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 8
waiting for 9
Use of uninitialized value in print at perl_module1.pm line 43.
waiting for 10
Use of uninitialized value in print at perl_module1.pm line 43.
WaitForThreads() finished
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
Scalars leaked: 1
LetsRock() ended

[download]

I'm at a loss to know what else to suggest. If you had a missing required package, I would expect you to be seeing an error message detailing that, not an exception.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^5: Threads calling LWP causes exception by BrowserUk
in thread Threads calling LWP causes exception by mojoshaneman

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