I got these statistics from the GCJ mailing list. Interesting to see that Kenya had the 2nd highest number of registrants.

Number of registrants by country:
510: Egypt
116: Kenya
100: South Africa
 48: Jordan
 43: Nigeria
 27: Ghana
 21: Morocco
 18: Syria
 16: Palestinian Territory
 16: Uganda
 14: Lebanon
 11: Algeria
  8: Saudi Arabia
  7: Togo
  6: Kuwait
  5: Tunisia
  5: Zimbabwe
  4: United Arab Emirates
  3: Ethiopia
  3: Israel
  3: Qatar
  3: Senegal
  2: Cameroon
  2: Canada
  2: Iraq
  2: Ivory Coast (Cote d'Ivoire)
  2: Yemen
  1: Burkina Faso
  1: Congo
  1: Iran
  1: Libya
  1: Malawi
  1: Mali
  1: Mauritius
  1: Mozambique
  1: Namibia
  1: Oman
  1: Pakistan
  1: Rwanda
  1: Turkey
  1: Zambia

 

These are unofficial statistics because some contestants might be ineligible, and some may have chosen to represent a different country from the country they live in, but the numbers should be pretty close to the truth.

 

Qualified competitors: 

Egypt 152
SA 33
Jordan 6
Lebanon 6
Ghana 3
Morocco 3
Kuwait 2
Palestine 2
Saudi Arabia 2
Syria 2
Zimbabwe 2
Algeria 1
Bulgaria 1
Cameroon 1
Emirates 1
Kenya 1
Mozambique 1
Togo 1
Tunisia 1
UK 1
Zambia 1
I can't confirm those numbers or competitors/countries are eligible, but I can confirm that the one in rank #28 (from UK) is ineligible, don't know how come.
If we remove him and consider the qualified are 222 competitors then:
Egypt -> 68.5%
SA -> 14.9%
Others -> 16.7%

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--This message represents the official view of the voices in my head--