Knitting Issues

I imported a legacy part ("Top Housing Before") that I wouldlike to modify (see highlighted "blue" surfaces). Using ImportDiagnostics I deleted faces and then tried to recreate new faces bypatching the 3D sketches and remaining surfaces ("Top HousingAfter"). I was able to knit most of the surfaces except the twosurfaces highlighted in "red". I tried several methods (tried tosplit and patch smaller areas) without success. I can see smallgaps between the surfaces but I was unable to heal the gaps.

I have had few other issues with surfacing.
1. Once I started adding the features to imported part, I wasunable to go back to Import Diagnostics (the option was suppressed)and modify imported surface. I had to delete all thefeatures/changes (suppressing the features or rolling back did notwork) before I could go back and modify the imported surface again.It would have saved some time if I could use Import Diagnostic toolinteractively.
2. Once I stated knitting the surfaces, other near by surfacesstarted shifting. Please see screen shots before and afterknitting. Is it something typical?
3. How does on pinpoint area or highlight surfaces that are causingproblems? (e.g. in Import Diagnostics the invalid faces and gapsare highlighted). I tried using Tools/SystemOption/Performance/verification on rebuild without success.
4. Is there a simpler or different method one can use to modifyimported parts/surfaces?
5. How do I minimize the file size? The file size increased inexcess of 60+ Meg in one case.

I would appreciate any help you can provide. Thank you.

SW 2009 SP 2.0
Dell Precision 380
Intel Pentium 4 Processor, 300 GHz
2 GB, 533 MHz, DDR2 SDRAM
nVidia Quadro FX 3450, 256 MB PCIe

SolidworksSurfacing