Laws and regulation
The rules of Nauru are based on the modern framework act on gambling and by-laws that introduce mandatory licensing for organizers (lotteries, bingo/raffles, board games, etc.), the age limit is 18 +, requirements for posting a license and keeping records.
For local charitable activities, there are exceptions for "small" games (small prize pools, one-time fees).
The financial side falls under the AML/CFT circuit: KYC, sources of funds, reporting.
There is not much full-fledged domestic industry; online casinos and betting sites usually operate from outside, and without local permission remain outside the national consumer protection zone.
Practical vector - point licensing of charity draws and control of payments/advertising, as well as informing players about the risks of offshore platforms.