I tried to receive an answer to my problem on using the Pro version of LimeWire.
As suggested by LimeWire I did contact services@LimeWire.com
I spent time for no result : the only answer I did receive was an automate message telling me to submit my question on the forum ...
The conclusion is you can pay for downloading the "pro version" but you may help yourself if you have a problem !
Thank you LimeWire : your customer policy is fair and shows a large respect for your customers
Does anyone feel the same than I ?