Hi.
@ PostFreeOnline.Com
If these notices are apearing in debug.log, you should disable the debug and leave them as they are(harmless).
If you have (like I do) a log folder on your host plan in which all these are building up then you can resolve them but remember that if you do any update to the osclass or plugins, you will have to remake them....
As you resolved the previous notices, you could do it by your self with if ( isset (argument)) or instead of isset use is_array if the argument is an array writen like like $name['key'] or $name[number].
@ Aficionado . I want to become a junior developer asap, but I'm not a member of the osclass team of developers.