[Alfa1]

Your image gallery is getting hacked. He was able to upload files to your server. What software do you use for your image gallery?

I see your hacker asks you to remove safe_mode and mentions your permission settings.

You need someone who knows what he/she is doing to review your server security. Ranging from permissions to the services that are allowed on your server. Your logs need to be reviewed, so that you can see what happened and what security issues you need to resolve. As I see it you have two options: get someone in charge of your server security or you will have to learn it yourself(either by free will or by force, as hacks will likely keep on coming)

Although I do not know the situation, my bet is that the hosting co has no clue.