2. So a negative non-UL BeL suggests profitable business? But the overall BeL is still positive ie unfavourable, so why is the business profitable?
I wasn't talking about a 'non-UL BEL', but about the non-unit component of a BEL for a UL contract. Recall that the non-unit component of a reserve for UL business is calculated as the PV of future {expenses + benefits in excess of unit fund - charges). Charges would probably be loaded up to make profit in addition to being sufficient to pay for expenses and excess benefits, hence this calculation would (on a best estimate basis) be expected to be negative.
I'm not sure why you believe that a positive BEL is 'unfavourable'. The overall BEL for a UL policy would be the unit reserve (= unit fund value) plus the non-unit reserve component (as described above) and this would very likely be positive in total, particularly once the unit fund has grown with premiums and investment returns over time. That's not 'unfavourable' for the company, as they will be holding the unit fund that backs the unit-related component of the BEL (as this is what claims paid out are likely to be based on).