>1. - Should I charge to this particular Client the "learning hours"?

One factor in deciding this is to determine your likelihood of re-using what
you have learnt about a particular thing. If it is about a system or process
peculiar to that client, and you are not likely to re-use it elsewhere, then
charging for the time is probably right and correct. In this case there may
be a point in itemising some of the costing as "customer process research"
or similar suitable wording.

>2. - Should I release the code to the customer who asks for it?

As others said, this is dependant on your contract. Go through the PIC
archives for a number of discussions in the last few years where others have
pondered this point. A starting point for your search will probably contain
the word "contract". Also remember that there are circumstances where you
should supply the customer with the code under your contract, but the
copyright of the code may stay with you, and the customer will be required
to protect it as your property. Again check the archives and see there what
others have had lawyers arrange in the contracts.

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