Wedding Forum - Music and timing - a question...

We are having a civil ceromony and this weeks job is sorting out the music.

The venue and the registrar have, separately, advised us that we need the following music:

For seating the guests - four songs
Brides entrance - one song
Signing the register - four songs
bride and groom exit - one song

So ten songs in total. My questions/concerns are:

1. Will they play all the songs? For example, I want Waltzinblack to play before my entrance music, I'm thinking that they will just play the 'seating guests' music until I'm ready to enter, rather than waiting until all the seating guest music is finished..
2. The music we want is mostly classical, so the song length can vary considerably, how long should a 'song' be? For example, I have about six different versions of pachelbels canon ranging from three to six minutes.
3. My 'aisle' is quite short....how does this work? If its (for example) a three minute song do I stand at the front waiting for it to finish.
4. Four songs for signing the register seems an awful long time to me.

I'm bamboozled with it all xx

we have choosen 8 songs. we are having Ave Maria - Christina England Hale
as i walk down the aisle. listen to it on youtube its beautiful x

When we chatted with our registrar she advised to pick 'a few' songs for signing register as it may take 5 mins, or may take 15 - so I think they will play the music for as long as the event takes then stop it.
Must be the same with guest seating music - playing until registrar is finished with her bride chat and ready to start things off.

Our aisle is also very short - registrar suggested we start playing music (actually someone singing) then bridesmaids come in one by one, walking slowly, page boy etc and I enter as the last verse starts so that me arriving at front and music ends about the same time. She also suggested bridesmaids in first on short aisles so that there isnt a pile up behind bride/train etc.
Hope something of that helps x

Sorry for spamming here - more thoughts popping into my head after i click post lol
4 songs sounded a lot to us but she explained , they sign something, bride and groom sign, witnesses sign.. and at that point the bride and groom resit and mock sign for photos - guests (with B&G premission) may also take photos then - so I guess that's why it can take 10 to 15 mins

Almost Mrs B aww no. im glad im marrying in a church then as i love that song, xx

We've been told 6 songs, 1 for me entering, 4 for signing and 1 to walk back out to.. I'm buying a piano music CD which is 3discs for the food so they can just pay one of those while guests are being seated xxx