I have co-created a company in the past, but as the engineer/maker. Most of the business and administration work was done by my partner. I am now creating a company entirely, and my partners are going to be peer engineers.
Engineers, even founding ones, should really spend their brains on the product. And I am one of them, with some level of vision and leadership in the "what should be done". I am practical with some ideas/practice already, but I would really appreciate knowing how you have dealt with that yourself.
Core issues are probably time management and priority negotiations. And all those issues surely depend on the timing and phase of the company. If you think this is too broad, I'll split the discuss into segments. For now, I "stated" the top-5 issues to focus on the core.
Engineers as founders tend to focus on the product/service they are designing - and don't have enough knowledge or respect for other aspects of their business. It is as though the three legs of the stool were uneven, with one leg being significantly longer than the other.
1: You need balance between marketing, finance, engineering and operations.
2: Engineers tend to have developed their scientific and math skills to the detriment of their social - people skills. They need help in this area.
3: Most Engineers turned CEOs do not know how to select and manage either their board or their executive staff. They need coaching.
WOW, this is a HUGE topic to tackle in a discussion form like this.
My first recommendation would be to read the book The E-Myth Revisited. This goes through in detail the struggles you are facing and how to handle them.
The bottom line however is you need to have someone on your team who understands business and operations, whether you bring them on full time or just contract it out to get you set up and going. You can not build a successful business just around technicians(engineers); you need an entrepreneur mind and a manager mind as well.
I'd be more than happy to talk with you further if you want to message me as I could give you more tips and resources based on your exact needs.