what key board settings may be changed at user account level?

In addition to the keyboard native to my MacBook, I use a detached Apple keyboard connected by bluetooth. Both keyboards are preventing the space bar from advancing the cursor in a few situations: 1) in spreadsheet applications (both Apple Numbers and Microsoft Excel), but only in a few of the cells; 2) in an literary reading and note-taking application downloaded from the internet that I've used on this Mac for 3+ years. This problem began a few weeks ago and nothing I've tried so far has resolved the problem. Attempted solutions include resetting settings to "default", talked to Apple Support, setting up a test user account, and deleting and re-installing all three of the applications in which the problem has been observed. Apple Support recommended setting up the test user account and deleting/reinstall the apps and has, so far concluded that it may be a keyboard mechanical problem. Even before deleting the apps, the problem did not occur in the test user account. After re-installing the apps, the problem still occurs in all three apps for the Administrator-user account. This leads me to believe that it isn't keyboard mechanical and that I must have inadvertently made an undesirable change of a keyboard-related setting in the Administrative-user account.