Use - Create Mode - URL error message
For the first part, see if this answer helps: https://civicrm.stackexchange.com/a/22434/225

For the second part where the profile is not showing up, that can mean that you have added fields that are not valid in the context where you are trying to use the profile.  Civi determines the type of the profile based on the fields it contains, so adding fields can reduce the places where it can be used.  Looking at your screenshot shows Testing_Only in the type so look at your fields and remove whatever relates to Testing_Only and see if that results in the profile showing up where you want it.