Updating Microweber is very easy 

Microweber has automatic update mechanism as of version 1.1.3, you just need to visit the marketplace section and click the update button.

For manual update, follow those steps:

1) You must download the latest zip from here https://2018.microweber.com/download
2) Then you must replace the folders "src" , "vendor" and "userfiles"
3) After that visit your site's admin panel 

If you find some problems, please report in the forum.