A11COS

My ST220 (3.0 V6) started an intermittent mis-fire on idle last week, this got progressively worse and on route to get the vehicle scanned it suffered total loss of power, it did start again but was popping back into air box and stalled, after AA patrol/technician could not fix, start or locate fault after replacing 7.5A engine management fuse with a 15A to stop it blowing? And checking for voltage etc at various locations it was recovered to my friends garage.
When scanned the diagnostics reader/scanner again couldn't connect with vehicle and the management fuse had blown again , with the use iof a resetable fuse and an auto electrician it was found that with the coilpack disconnected the fuse didn't blow when cranked ir ignition energused, I purchased a genuine coilpack and fitted it but still no start, the coilpack plug was checked for triggers on cranking and no signals were detected as no spark present at any accesabke HT lead (front bank). I removed the ECU and due to the burnt smell opened up the ECU and observed several damaged components/trans-sistors. The ECU was sent for repairs and on its return re-fitted it and the vehicle started first time but disapointingly still had a misfire, after warming up and another scan no new codes or faults were detected. I drove the vehicle home and its clearly not right with lavk of power. I went to Fords again yesterday and purchased 6 new plugs and fitted them but fault still present? The HT leads are 10mm and are app 6mths old, I disconnected them one at a time at coil pack and started engine and no difference, I also re-installed the old Ford HT leads and fault still present.
I'm going to call the ECU repairer today and explain the symptom but I'd really appreciate any other suggestions or recommendations ,
Thanks in advance, DJ