Hi,
How do you execute your script?
There are two actions on SQL editor toolbar - execute statement (Ctrl+Enter) and execute script (Alt+X). As you script is multiline an contains many statements it should be executed as script.
It seems that you just selected your delete statements and execute them all as a single statement. In case of Oracle it leads to "invalid character" error. But execute script action should work.
Ctrl+C doesn't work in error log view (clipboard copy avaiable only thru context menu) but it should work in execution log. At least it works in my environment. Anyway I'll test this issue.
Thanks!