The problem with one of us answering it is that it all depends on the policy and contract
Insurance policies are extremely complex and are covered not only by the language of the policy, but also the laws of the state. For instance, in Texas the insruance companies have a provision in the automobile policies that isn't effective in Texas. The courts and insurance commissioner have all determined that it is "against public policy" yet it still remains in the language.
The best way to be sure you are covered is to put everything in writing, send it to the agent and insurance company by CMRRR so that you have proof they received it, and only use agents who have errors and omissions insurance themselves.
Typically, all of your items would be covered by at least one of the insurance policies you discussed. However, if you have multiple insurance policies with multiple companies and one of them has a chance to shift the burden to another one you can bet they are going to try to do that. In addition, some policies exclude coverage on personal policies for incidents which occur during "business use". Whether your art would be considered business or personal depends on a lot of facts, but it is certainly something that needs to be addressed specifically, if not in the actual policy language at least in some manner.
Thank you for allowing me to assist you. I believe I have answered all of the questions you asked so I would request that you please click the ACCEPT button so I receive credit for my work and leave feedback if you have a chance. Please consider clicking "BONUS" as a nice way of saying "thanks" for a job well done, although this is neither required nor expected. Please remember that we can only base our answers on the information you provide and sometimes a misunderstanding as to what you are looking for or already know occurs so feel free to ask additional questions. Please be aware that my answer is not legal advice, it is merely information and no attorney client relationship has been formed. You should always contact a local attorney for legal advice.
Several customers have asked how they direct a question to me in particular. If you specifically want me to provide information for you just put “FOR TEXAS ATTY” in the subject line and I will pick up the next time I am online.