Interesting tidbits from a quick skim of that section.

11.4.2

In addition, the Occupying Power may not compel the inhabitants of occupied territory to become its nationals or otherwise to swear allegiance to it.

11.6.1

The population of an occupied territory, like other protected persons under the GC, are entitled, in all circumstances, to respect for their persons, their honor, their family rights, their religious convictions and practices, and their manners and customs. They shall at all times be humanely treated, and shall be protected especially against all acts of violence or threats of violence, and against insults and public curiosity.

11.6.2.1

It is forbidden to compel the inhabitants of occupied territory to swear allegiance to the hostile State.

11.8.3

The restrictions placed upon the authority of a belligerent State cannot be avoided by a system of using a puppet government, central or local, to carry out acts that would be unlawful if performed directly by the Occupying Power. Acts induced or compelled by the Occupying Power are nonetheless its acts.

11.8.6

It is immaterial whether the government over an enemy’s territory consists in a military or civil or mixed administration. Its character is the same and the source of its authority the same. It is a government imposed by force, and the legality of its acts is determined by the law of war.

11.20.1.1

The Occupying Power may not compel protected persons to serve in its armed or auxiliary forces. No pressure or propaganda that aims at securing voluntary enlistment is permitted.

This one seems like it could be a big deal:

11.22.2.1

Contributions may not be levied for other than the needs of the occupying forces and the administration of the occupied territory. For example, contributions may not be levied:

• for the enrichment of the Occupying Power;

• for the payment of war expenses generally;

• for the purposes of collective punishment; or

• for the purposes of impoverishing the population in order to pressure the enemy to sue for peace.

Also important:

Under 11.22.5

The Occupying Power’s powers to regulate currency must not be used to confiscate private property. For example, intentional debasement of currency by the establishment of fictitious valuation or exchange rates, or like devices, as well as failure to take reasonable steps to prevent inflation, with the result of enrichment of the Occupying Power, would violate international law.