Hello federico.furlani,
I'm guessing you mean that the download link for PLUS+1 Update Center contains version 1.0.188 and not 1.0.190? Good question and I have no good answer for you.
This shouldn't really matter, because PLUS+1 Update Center should automatically update to the newest release after installation.
If you do update to 1.0.190, don't click the button in the web browser that shows up, I believe it confirms that you are logged in and the button should direct you to the PLUS+1 Tool. Just close the browser and use the tools you need. Some user have got an error pop-up they need to confirm, but it ends up behind the Update Center Window and they can't click OK. If this happens, use the task manager to end the tool and restart. It should work after that.
This issue is fixed in the next release.
Have a nice day.