My workbook consists of 1 sheet with about 1400 records and a userform with controls to access / edit these records. The userform works very well

I want to revise the layout of the userform and I made a copy to do the changes on the copy first but as soon as I try to re arrange some controls (texbox / labels) Excel (2013) crashes and have to start over again. The copy I made is in another directory with the same file name which after a few crashes a change the file name but the problem persist

Am I doing something wrong?