How change property in a modelitem using a button

Hi Alberto, could you elaborate a bit on your use case if i follow you right you are attempting to update e.g. a Thing's property via certain input from a Mashup?

Based on what sort of entity and its property you are trying to update you may be able to use one of the out of the box service from that entity and you can bind the input from button & other application parameters to this service as an input. Thus clicking on button will invoke that service taking required input and in return updating/creating required properties for the entity.