I had a contractor install a roof with 30 year Owens architecture shingles. Several questions 1) Put wrong color drip edge all the way around perimeter and has to replace is this a problem? 2) Several areas gaps about 1/2 inch to a inch in shingles and you see the tar strip from the shingle below is this a problem? 3) Numerous shingle have dime size wear marks on like they are defective they have no granules it looks like what the back of a shingle looks like. Should they have been put on and could they cause a problem down the road. The contractor is going to replace drip edge, the gaps contractor said was no problem and would not cause any problems and the shingles he said were defective and he would put a dab of roofers caulk on bad spots. Is this acceptable for something I have paid big money for. Any help or suggestions would be greatly appreciated.