This trainer has been made for Chicken Invaders 4.
It should support most game versions, tested with v4.0

Trainer download link:
Chicken Invaders 4 +4 trainer
Chicken Invaders 4 +5 trainer (added an option to get 5000 keys and so You can unlock all stuff)
Chicken Invaders 4 +8 trainer (added instant kill, weapon power and no weapon overheat)

First run the trainer.
Then run the game. (You can start the game with it's own icon or You can use the Start game button in the trainer.)
Hit the number keys on the keyboard to turn options on/off.
You can also use the checkboxes to enable/disable the options.

There are 8 options in this trainer:

1. Unlimited Health
2. 100000 scores per kill
3. Max food
4. Unlimited Missiles
5. Get 5000 keys.
6. Instant kill
7. Weapon power
8. No weapon overheat

NOTES:

Unlimited Health: If You get or loose a health, You will have 99.

100000 scores per kill: You get 100000 scores for every kill.

Max food: Your food is on max. Every time You get food, You get a missile for it.

Unlimited Missiles: If You get or use a missile, You will have 9999.

Get 5000 keys: When You get a key, You will get 5000 instead of only 1.

Instant kill: One shot will kill any enemy (including Bosses).

Weapon power: Max weapon power. You need to collect a weapon upgrade to take effect.

No weapon overheat: Your weapon will not overheat.

As You can see, every cheat will take effect when the amount of health, scores, food, missiles etc is changed.

WARNING!!!
Some guy seems to be using my trainer to spread some suspicious file using this site:
http://www.chickeninvaderz.blogspot.hu/p/chicken-invaders-cheats.html
Do NOT visit the site, do NOT download the file, because it is not the original file that I have posted here and if you get a virus from there, bad luck. Impostors and scammers are all around the net so if you want to download any of my trainers, best to do it from this site instead of somewhere else where anyone could have reposted it as a virus.

You can send Your comments and bugreports to Ezt a címet a spamrobotok ellen védjük. Engedélyezze a Javascript használatát, hogy megtekinthesse.

Some information about virus reports for trainers generally. Read it before You post something about some virus.
http://szemelyesintegracio.hu/cheats/41-game-hacking-articles/212-trainers-and-anti-vir-softwares