I've tried to modify the module. First I installed the module then I extracted the source code. Then I added existing project source code into the DNN project. But when I modified the VB file, it doesn't have any effect on the website (like it's not getting the changes e.g add label cannot display the text that is set from the vb file). Where can I find guide to modify your source code (I need to change the tagging so it doesn't split when have more than 1 word)

Thank you for your response
I've tried the BlankModule solution but still cannot figure out how to setup simplegallery 02.03.04 source folder
There are several folders  and ascx and vb files in source folder. So how to place them in DNN installation folder?
Can I just extract them all in same installation folder of simple gallery private assembly or must it be in different folder
then later need to add components in Create Module 1 by 1 (duplicating the setting of private assembly)?

Is there any way to install the 02.03.04 source module (e.g. another dnn file that doesn't throw error when
try to install the source module) so that I can change the VB files later without interference from dll?
Basically what I need is to change the code in EditPhoto.ascx.vb from lines 381 to 398 so it doesn't split the tags (have tried this but get difficulty when trying to integrate the whole thing because don't know the right setup)

Finally, I can change the source code. Basically I created the blankmodule solution. Then installed the simple gallery module. Then I extracted the source file to the directory of SimpleGallery. After that open the blank module solution and add the Ventrian.SimpleGallery.vbproj. At the end changed the code then rebuild the dll.

Now the problem is how to migrate this dll to live site. I tried overwrite the dll from the installation file but it throw error. I also tried create new package for each simplegallery module (main one, tag, random) and install to overwrite the current module but it didn't work. Later I will try to use backup the live website then use the blankmodule approach to make the changes.

Thanks for your help