Hi Aldrin,
Other developers already replied your post in detail.
Here are some examples of mdlElement_setSymbology() function usage from MicroStation V8 MDL Function Reference. If you don't want to use some parameters, you may pass them as NULL. You may find some examples in this documentation or use delivered examples with MicroStation SDK to be able to understand better usage of functions.
MSElement element;
UInt32 color;
UInt32 weight;
Int32 style;
mdlElement_setSymbology(&element, &color, &weight, &style);
mdlElement_setSymbology(&element, NULL, NULL, &style);
mdlElement_setSymbology(&element, &color, &weight, NULL); Regards,
Ahmet Sedat ALIS