How to remove a web part causing page to error out

When a web part page or a content page gives an error possibly because of a web part,
we need to remove the web part. To get the current page into maintenance mode
issue the following:

?Contents=1

Example:

http://testsite/customers.aspx?Contents=1

Custom Content Types and Page Layout in Variation

Variation works good if we are using OOTB content types and page layouts.
However if we have custom content types and page layouts, we will need a
Custom Site Definition with custom content types and reference to page layouts.

Copying documents from Variation Source

Do you need to copy documents from variation source site to other variation sites.
Can it be an Automatic copy of docs?
Yes, provided the following condition is met i.e.

If the URL to the document is in Publishing URL field on Page Layout,
on creating a new page using this Page Layout, add a link to the document and save.

Approve the workflow and magic happens - The document also gets copied to all variation sites from this source variation.
Same is true for Images from Image Library.

Unfortunately List Items will not get copied automatically and we will need custom code to do that.