LSMW update or delete contact person in business partner

HI Guys,

I have created a project in lsmw that updates the business partner. A subproject that update or insert contact partner relation. I would like to know if I can set the OBJECT_TASK in coding and set the field to 'I' or 'U' depending on what i have received in the input file. The same is for communication(email, tel, fax,...) data in the contact partner relation. Can I set the field TASK in coding to 'I' or 'U' depending on my input in the import file?

I have seen examples only with OBJECT_TASK or TASK as constant 'I' or 'U' or 'D'

What are the incovenient of LSMW?

What should i be aware of while using it?

Thanks and best regards