How should a long sentence with multiple "or"s and commas be understood?

I'm trying to get a proper understanding of exactly what a long, run-on sentence really says. The actual text is from Michigan law, but I'm not seeking a legal interpretation rather a full understanding of the grammar.

The full text is ADVERTISEMENT OF AGRICULTURAL ADVANTAGES, but the part which of interest is

... an amount to be used for advertising agricultural or industrial advantages of the state or county or any part of the state, or for collecting, preparing or maintaining an exhibition of the products and industries of the county at any domestic or foreign exposition, for the purpose of encouraging immigration and increasing the trade in the products of Michigan, or advertising the state and any portion thereof for tourists and resorters. ...

For what specific things may "an amount" be used for?

More to the point, is/are "for the purpose of encouraging immigration ..." (an) enumerated activity (activities) of its own? Or, is does it qualify the activity before it? Is the text is any way ambiguous? If this were to be re-written as a bulleted list, how would that look?

The detailed technical reasons supporting any particular reading would be quite useful.

Solution 1:

It appears to mean the following

... an amount to be used

• for advertising agricultural or industrial advantages of the state or county or any part of the state, or

• for collecting, preparing or maintaining an exhibition of the products and industries of the county at any domestic or foreign exposition, for the purpose of

   a) encouraging immigration and increasing the trade in the products of Michigan, or
   b) advertising the state and any portion thereof for tourists and resorters.
  

While the interpretation of complex and ambiguous laws keeps numerous lawyers busy and well paid, Courts tend to look to see if there is parallel construction to interpret what the legislature intended.

In this case, the start of the first main category is designated by for and the next is set off by , or for. The for in the purpose of phrase is not part of that series of main categories. If it were part of a series, either the second category would not have had an or and the purpose of clause would have begun with one, or all the phrases in the series would have begun with or.

SUPPLEMENT

It has been suggested that the portion I have listed as subparagraph b) should be its own bullet as a main category. [See @Dan's comment below for the rationale.]

There is some common sense logic to that, but I don't think so for two reasons. To be parallel, it would need or for, which it lacks. Also just to advertise the state ... for tourists ... seems broader than the product focused criteria of the other two main categories. (And now we are into legislative interpretation for which we need to charge lawyers' salaries.)