They look generally healthy; I think the browning flower was probably coming to the end of its bloom time, when they will gradually brown and fall off. Browning buds may mean they need watering daily, especially if they get a few hours sun in the mornings and the sun is hot (even if the air temperature is reasonably cool); Fuchsias prefer partial or dappled shade to grow well. They should be given a good watering when you do it, enough for water to run out of the tray at the bottom, so if you've not been doing that every other day, try that before you start watering daily, but the foliage does not look as if it's suffering drought, and there are plenty of healthy buds and flowers.
I'm not seeing brown spots on the foliage from either of your images, or did you mean brown flowers?
UPDATE:
If you're watering each one with 2-3 litres of water every other day, that should be adequate, so don't increase watering just yet. Feel the top of the soil on the second day to see if it's quite dry to the touch - if it's not then don't increase watering.
The browning buds could be due to very windy conditions, or very hot sun when you first planted because they were not used to it. The other possibility is cold over night temperatures - both your fuchsias look to be tender varieties, and the buds will shrivel if it gets too cold. If it's really cold (frosty conditions) some of the leaves might brown too, but I imagine serious frosts on a regular basis are unlikely at this time of year where you are.