Added a few missing argument/parameter checks

Signed-off-by: IUnknown68 <arne@salsitasoft.com>
Removed argument check

Signed-off-by: IUnknown68 <arne@salsitasoft.com>
Removed argument check

Signed-off-by: IUnknown68 <arne@salsitasoft.com>
Merge pull request #13 from salsita/develop

Added a few missing argument/parameter checks