Thank you for reporting this issue to us.
I have logged the first reported issue into our feedback portal and you can check its progress and vote for it here: Image manager doesn't display the correct size of the inserted image
. I have also updated your Telerik points as a small sign of gratitude for your report.
Regarding the second issue - it is caused because of a general programming limitation and cannot be controlled by our controls.I would suggest that you review the following help article that provides more detailed information on the subject: Restricted Symbols
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