Use imgur.com They are free, you don't need to open an account and it's just a matter of getting the image URL then inserting that URL into a post in here.

Don't use your local DropBox/OneDrive URL as only you would see the image. A public URL is needed.

Just paste the sequence of characters taken from imgur (or your other image hosting site) that looks like this:

[img]https://i.imgur.com/X9pAwC6.png[/img]

Hey presto. Your image appears!

Thanks for your reply...

I try it again and the problem remains, if you try to change the shape using the right click on a object as you advised. I also try it to change border style on the new version but it does not exists either. I send you a screenshot to your email.

My fault was that I was not aware of the properties icon.

Looking forward for the new version :-)

You need to ensure you right-click the object and not the shape. Best to right-click the block title or somewhere in the middle.
In order to show Block Properties on right-click, a block must be selected.

@Georgios Asimakos

Better using with dimming.