Characters that are manually typed into a tool settings text field such as the Place Active cell field within the Place Active Cell tool are consistently removed. It is almost like the field refreshes and removes all typed content.The issue will not occur if typing a valid entry such as the full cell name, but if typing anything else other than a valid entry, the issue persists.
The AutoUpdate feature must be turned off. To do this, set configuration variable MS_AUTOUPDATETEXTITEMSSUPPORT to 0. Here is a sample workflow:1. File>Settings>Configuration>Configuration Variables>All Category>MS_AUTOUPDATETEXTITEMSSUPPORT2. Click Edit3. Enter "0" without the quotation marks into the New Value field. Press OK, then OK again. Select Yes to save changes to the Personal.ucf.4. Fully close/reopen MicroStation for changes to propagate.
This configuration variable turns the AutoUpdate feature on for text items on those dialogs and tool settings that want this feature. "Text items" are text controls or text input fields on dialogs and tool settings windows. If set to 1, text items are automatically synchronized with their values without focusing out. For example, while placing a circle, in the Place Circle tool settings window, if you enter a value in the Diameter text field, the cursor displays the circle with that diameter. If you change the diameter in the text field, the size of the circle changes to the new value automatically.
MicroStation CE Online Help - Operation Configuration Variables