Currency modules conflict?

I have Booster Plus. Most of my products are in CHF but my sales are primarily Australia and some NZ.

Originally I set up Prices & Currencies By Country module with IP detection and currency selection. After some days with no evidence of a currency selector showing, I turned that module off and set up Multicurrency (currency switcher) and use the widget to successfully display choice of AU$ or NZ$ on home page and shop etc pages. It worked fine on my PC.

However I now find that the currency switcher does not display on PCs I used in NZ and Aus to test the modules. Both NZ and Aus PCs display AU$ pricing with no switching on offer.

Have cleared the cache on each PC and in WordPress to no avail. I also tried having the Prices & Currencies By Country module switched on again (despite having to set the AUD/NZD conversion rate in it and currency switcher, perhaps implying that maybe they shouldn’t be on at the same time) – also to no avail.

I asked a friend who has not previously accessed the website to do so. There was no currency switcher available. This seems to indicate that I have an incorrect setting. I have searched re-searched settings but cannot locate any that has a bearing on the issue excpet perhaps the following.

Does the choice of currency, whether via IP or selection remain in force and thus prevent the switcher showing again? If so, does the ‘Revert Currency to Default on Checkout’ switch resolve that issue?

In case there is conflict between modules, here are the 9 modules I have active;
Checkout Custom Fields
Currencies
Currency Exchange Rates
Empty Cart Button
Export
Gateways by Currency [unsure if I need this – no info available on why or why not]
Multicurrency (Currency Switcher)
Multicurrency Product Base Price
Order Min/Max Quantities

btw if you are wondering why I want currency switch to continue showing when a user returns to the website, it is because I have customers who sometimes will pay in their home currency and other times wish to pay from their bank account in the other country.

I’m stumped. Please help.

The page I need help with: [log in to see the link]