Hi Weigo, I am having the same issue as Rajesh.
I installed EXPORT and IMPORT plugins on two OctoberCMS sites. On the first site, I exported my custom plugins and theme to zip using the EXPORT plugin. On the second site I imported the same files using the IMPORT plugin.
When I import the plugins, the screen loads and refreshes, but there are no visible messages, the plugins do not get installed, and there are no event logs.
When I import the theme, after the page refreshes I receive a red error banner stating "Error Extracting Archive".
The import plugin does not appear to work. Though, the EXPORT plugin does seem to work.