transfer of investigation from police to excise officials in the middle of investigation

[jithendhar chiranji]

Sir/Madam
In Adilabad Dist. in 2013 the then SP of Police had issued a circular to his subordinates to transfer excise cases to excise department for investigation.
After that police are registering the cases by issuing FIRs, arresting accused, remanding them, sending the samples to FSL.
At this stage, basing on the said circular of SP, police are handing over the cd file to excise officials for further investigation and filing charge sheet.
Excise officials, for the best reasons known to them, receiving cd file and issuing COR at such stage and keeping the investigation pending.
Due to various reasons, several of these cases are remaining as such without charge sheet being filed.
Recently in few cases, excise official had filed charge sheet in such cases.

Now my questions are:

1. FIR and COR are equivalent in law. Hence, can there be two information reports of various dates in a single criminal case as to single offence?
2. Can a single criminal case be investigated partly by two different departments (police-home & excise-revenue)?
3. Can a police officer who assumed role of an IO lift his hands from investigation in the middle of it and throw the responsibility on others, without there being any special reason or ground, except that there is excise department dealing specially with excise, even though police have simultaneous power?
4. what authority an SP has to issue such circular directing excise officials to continue investigation in cases initiated by the police?
5. what authority an SP has over excise department?
6. as excise official is simply basing on the investigation done by police to file charge sheet, without anything specially being done by him, whether his charge sheet as an IO is lawful and valid, in these circumstances?
7. when police have simultaneous authority as per excise laws, can they transfer the cases as such in the middle of investigation, without there being any specific legal procedure for that?
8. If the act of police is correct, it should be vice-versa. So can an excise official direct further investigation by police, in cases initiated by them?
9. finally now what should be the fate of charge sheet filed by excise official in cases initiated by police?
10. If charge sheet should not be accepted on the ground of vitiated investigation procedure, what should be the fate of offence occurred?

I have one more legal doubt - can this kind of situation be referred to High Court u/s 395 Cr.P.C?

please put forth your valuable opinions over these....