There are a number of resources on this issue online. I've tried to list the best places to look below. I'll try to hit a few of your points:
1) Schools really have different policies, but you should absolutely apply. Canadians tend to need higher stats than average to get in to DO schools, but you already have that. I would honestly look at each school's website or contact each school to see their policies. That website is good, but who knows how up to date it is.
Looking at the Canadian Osteopathic Association' s FAQs, this is stated "
NOTE : If you are a Canadian interested in applying to AACOM schools, the AACOM has confirmed that the following colleges of osteopathic medicine may accept applications from Canadians that do not hold U.S. Permanent Resident Status (contact your school of interest directly to confirm eligibility): ATSU-KCOM, AZCOM, CCOM, DMUCOM, KCUMB-COM, LECOM-Erie, LECOM- Bradenton , LMU-DCOM, MSUCOM, NSU-COM, PCOM and GA-PCOM, PCSOM, TouroCOM-NY, UNECOM, UNTHSC-TCOM, VCOM, WVSOM, and WUHS/COMP (For more detail, please see 'Documents' page for link to document 'American Colleges Accepting Canadian Applicants')"
2) As people have said, MSUCOM has seats specifically set aside for Canadians. I would absolutely apply to MSUCOM.
3) As far as residency goes, yes you will run into some issues. First off, you'll want to do an ACGME residency (hopefully by 2020 of things go as planned all residencies will be ACGME accredited). This means that you will have to struggle in terms of finding a place that will take you as a DO and in terms of finding a place that will take you as a foreign national. That said, you will absolutely be looked at better by residencies as a US DO foreign national than an IMG foreign national.
Also, as a US DO graduate, you will be eligible to apply to Canadian residencies, and for both Ontario and BC, you will be able to enter the first round of the Canadian match alongside US MD and Canadian MD graduates. Foreign graduates must enter a second round of matching after the other graduates have matched. That said, obviously you will not be looked at the same as an MD, but as a US DO you will likely have a better shot than an IMG in those provinces. The thing is, you probably have a better shot at completing a US ACGME residency in that situation and just returning to Canada afterwards, but it's another option.
In any case, your options really are the following:
Canadian MD =/> US MD > US DO > Foreign (i.e. not North American) medical school.
Canadian Osteopathic Association:
http://www.osteopathic.ca/index.htm
http://www.osteopathic.ca/faq.htm
Canadian Osteopathic Medical Students Association:
http://www.studentdo.ca/drupal_beta/
http://www.studentdo.ca/drupal_beta/faqs
British Columbia Osteopathic Association:
http://www.osteopathic.bc.ca/