Hi Richard. To add to Musky's advice, as standard the dynamo is chain driven and runs in grease. There is felt or cork washer under the large dynamo drive gear to act as a crude seal. Your bike has a belt drive? an aftermarket mod, and oil should not be in that compartment.
The dynamo seals with a large cork washer against the inner timing cover. After tensioning the belt, press the dynamo against the inner side of the cover to trap the cork washer and seal this joint.
The oil pump runs in its own little oil filled compartment, so a cup of oil here is normal. Gasket faces failing to seal is common, the mating surfaces are narrow, and there are locating dowels which can bottom before clamping the gasket, especially on engines built from a collection of parts, and dowel locations full of old jointing compound.
Removing the inner timing cover means removing the dynamo drive gear....the cover will come away complete with the retaining bolts undone, but the idler timing gear needs to be replaced with the timing marks aligned, and so needs to be separated from the cover unless you have X Ray eyes. A better scheme is to remove the dynamo drive gear first, and check if the seal has been fitted. Then removing the inner cover will not disturb the timing gears if you are careful. Make sure the cover retaining bolts don't bottom.....incorrect lengths and old jointing compound at the bottom of blind holes all contribute to a lack of clamping force on the gaskets.
Swarfy.