need help please. just got to drive my x5 4.4 found a few problems

[Rabbit]

i have been in the middle east for the last 4 months. when i was gone i got an 2003 4.4 100,000 miles. i got lots of the mods ready to start putting on. but i came across a few small problems that i should look into and take care of first. here it goes

i had the oil changed with the recomended oil and ammount.the first time i drove it it had a small hint of oil burning when i stop and little when i drive. i guess its a valve cover gasket but i opened the hood and it looks like it will take some time to get threw all the plastic. any thing i should look for on my way in?

also after a few times driving and turning it off, i started it up and herd a slight knock. like the top=end did not have any oil in it for 1-3 sec. then it went away. it only happened once.

now that i herd that i seem to hear a slight knocking / tapping sound at idle. i dont here it if i give it just a little gas.

and when i back up i hear the reverse sen going off. it goes crazy making all kinds of bells inside, and will not stop for a few min. i hit the botton and it goes off. is there something i can fix that goes bad?

last is rear drivers side back looks to have milldew in it. i took the back side cover off to change the taillights and found a little moister. i will take pics but dont know how to add to the page. tell me how and ill do it thanks.

any help in part of in full would be nice. i am going to do all my own work on this to fix it. but if it takes a little more help i have a few good friends to help as well. please help thanks