Mac – Restoring selected files from time machine backup of a different mac

Here's the situation so far:

• 20" Alum iMac 2007 HDD has died (3 days after I got a new Macbook Pro – coincidence, or suicide?)
• It had a time machine backup on a regular external drive
• I have connected that external drive to my new macbook
• I tried Migration Utility but it wants to copy all files
  • Q1: Is there any way to make that thing break down to the individual folder or file level?
• Giving up on Migration, I want to use Time Machine to restore
  • I read somewhere that I need to use the Browse Other Time Machine option …
  • But I can't even run Time Machine without setting it up, so I do – I turn it on and point it at my external drive with the old time machine
  • Q2: Uh oh – wait a minute, is it going to wipe my old backup and replace it with backup of the new machine?
• I turn off Time Machine quickly
• I add a new external drive to another usb port and set up That one as a Time Machine backup for the new machine – turning TM back on.
• More research and I find out that I can get at the Browse feature from the Time Machine icon in the dock. (Why not from the system bar!) Anyway, I put TM in the dock, right-click and sure enough – there it is.
• Now I select my old external TM disk and start to browse
• The Today backup shows only stuff on my new macbook
  • I guess I created that when I selected it
  • But I'm hoping it didn't overwrite my old backups of the old machine
  • I see on the timeline on the right various dates going back but I can't select them

• Q3: How do I get access to those previous backups – I can see them there in the timeline but can't browse to them (back arrow doesn't work, nor does clicking in the time line – they're all faint purple)

• Now in desperation I look at the old TM drive in Finder – I can browse to the backupdb and see backups for the dates

  • But these dates seem to only include files which I worked with on those dates
  • That kind of makes sense for a backup – but …
• Q4: … is there a way to merge all the date folders in Finder to get the latest version of the folder? Or is that only possible through the TM UI (which doesn't let me access – per Q3)

Really finding TM to be very frustrating when moving to a new computer.

[Update] I found something. It turns out that the reason the backups are there but not selectable in the timeline is to do with the (frustrating) TM UI: It requires that you navigate to the right directory to see it's history.
I found this out from the tan coloured box on this page: http://pondini.org/TM/E2.html

The problem is that the directory structure is not the same on my new machine. I want to explore and retrieve things from the root directory on the old machine. What's more, the user directories like Documents and Pictures are not the same – even though i am using the same user name on both machines, so the path is the same /Users/me – so I can't see the history, of say, Documents.

However, if I click on the All Files link in Finder I can see old files from my back up and can go back through the timeline. But how I do I get at the folder structure.
To sum up:
– I have my TM disk from my broken iMac attached to my new macbook pro
– I have TM running on the new machine with a different disk and the icon in the doc
– I right-click and Browse Other Time Machine disk and can select the old one
– I see a bunch of backups in the timeline but they are greyed out (actually, light purple, if we're being precise – non selectable anyway)
– If I click on All Files in Finder now, I can see the backups of the files
But I really need to be able to explore the file system, not just from the unorganized All Files.
Note that I tried making local directories with the names of dirs I know to be in the TM backup, but that doesn't work – it recognizes, I think, that these are not the same dirs.