struct FlxPluginHeader {
	char Id[8];
	unsigned short LoadOffset;
	unsigned short EntryOffset;
	unsigned char PluginMode;
	unsigned char Reserved[3];
};

	Header of Plugin for Flex Navigator v1.xx:
		8 bytes Id - identifier of plugin, you should begin from three symbols - FLX
		2 bytes LoadOffset - displacement in page of memory for load (0 - 0x3FFF)
		2 bytes EntryOffset - displacement in page of memory for executing (0 - 0x3FFF)
		1 byte  PluginMode - modes of work:
				0 - repairing Flex Navigator screen after finish 
				1 - without repairing Flex Navigator screen after finish 
		3 bytes Reserved 
	length = 16 bytes

	ATTANTION!!!
	1. Size of plugin code (without header) must be less 4000 bytes.
	2. ORG = 0xC000
	3. When control will return to Flex Navigator, Carry Flag are specify error status:
		CF = 1 error during initialization
		CF = 0 no error