I’ve made some extensions and installed them on Slicer.
They are not easy to install. Is there any way that I can make an export of my current version of Slicer?
So, when I give them others and they install it, the extensions will be there.
I would recommend to submit your extension to the extensions index. That will make the extension available for users by a few clicks, in current and future Slicer versions, on all platforms.
Slicer is portable - it does not require installation but can run from anywhere (even from a USB stick). Therefore, if the extension private then you can distribute it by simply copying the Slicer install tree to the user’s computer.