If I understand correctly, You want
1. to create a folder at a location on button click and want to store the path of this folder in registry
2. Later you want to read this folder path from registry
As you already know how to create folder using BROWSEINFO, I will assume that you are struck with reading and writing data via registry. Here are few links for doing it:
For Writing[
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For Reading[
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or more options are here :
http://stackoverflow.com/questions/34065/how-to-read-a-value-from-the-windows-registry[
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