Drupal 7.x

Hi.

I've tried installing d7 beta 1, and I'm getting an error, but I'm not sure if it's an issue with drupal, or something I'm doing?

I'm new to the community, and wasn't sure where to turn for help, so apologies if this isn't the correct place (please point me in the right direction).

I need to reference a vew in a content type, this 's possibile in the older version (6.xx) but i'm not able to do tht in the Drupal 7.

We are a price information company based in India and want to get website developed in PHP regarding information on prices for all the goods,services,govt. fees and charges in India.
Looking for right persons for this job with all technical aspect.
Requirements:
1) Some websites can give better idea about our requirements e.g. pricegrabber.com, wishabi.ca and streetprices.com
note : above websites do not have services part as they mostly cater in line to products.

Is there have drupal 7 Class API ?
I want to find class method description quickly with Class API manual.

I've done some searching on this subject, but most of what I've found is related to Drupal 6, and of limited value to Drupal 7.

I am working on a large project with thousands of pages of content to port over to Drupal 7. I need to be able to say that 'this role/user/whatever' has control of 'these nodes/entities/etc'.

What are some ideas on how I can do that?

The Taxonomy Access Control module would work great, but it doesn't seem likely to be ported to D7. Likewise with the Lite version.

I'm evaluating Drupal 7 to do a web project, and i can't see in the documentation how to do theese things:
1. Is it possible to attach files to nodes or content types?

2. Another question, if it is possible add to a variable number of child nodes to a node. The child node can be a node type with fields: title, file,etc

Thanks