A single click on the image in the bin, a double click on the clip in the sequence OR a right-click on the sequence clip|CHANGE DURATION will launch a box under the preview window. Change length there.
Dragging should not be disabled. Assuming that you have saved the project, restart Videopad with no content. Under OPTIONS menu|DISK tab, Clear Unused Cache Files. Then reload your project. Always use SAVE AS, not simply SAVE, with a unique name or #, so as to not overwrite earlier versions.
