Thank you for writing.
Please find the answers to your questions in the same order:
1) I have not managed to reproduce the described behavior. Please send me more details about your scenario. Or even better, could you please send me a small example application that demonstrates it. This will help me investigate the issue and address it in the future versions. Currently, you can try to avoid the DropDown size problems by setting explicitly min size. Please review the code-block below:
|this.radMultiColumnComboBox1.MultiColumnComboBoxElement.DropDownMinSize = new Size(0, 300);
2) I confirm that the described behavior is not very convenient. We will improve it in the future versions of RadMultiColumnComboBox control. I have update your Telerik points for bringing our attention to this.
If you have other questions, do not hesitate to contact me again.
All the best,
the Telerik team
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