Debian packaging: custom file extensions for lib* package

I'm a newcomer in debian packaging. Currently I'm making attempts to build deb packages from C++ (and Cmake configured) project providing some shared library.

The problem is non-standard extension of the library: we must append .cocaine-plugin instead of .so to the library name due to requirements of the Cocaine framework that we rely on. So I managed to build the package, however there are several problems with the one:

1. The resulting library is too heavy due to error: E: libcocaine-plugin-pgconnector3: unstripped-binary-or-object usr/lib/cocaine/pgconnector.cocaine-plugin


2. The *-dbg package is empty: W: libcocaine-plugin-pgconnector3-dbg: empty-binary-package


3. ${shlibs:Depends} section is empty too.

Some of the configuration files that I use:

debian/control

Source: libcocaine-plugin-pgconnector
Priority: optional
Maintainer: Name Surname <name@corp.com>
Build-Depends: debhelper (>= 9), cmake, cdbs,
    libpq-dev, libboost-dev, libboost-system-dev, libev-dev, libmsgpack-dev,
    libcocaine-dev, cocaine-framework-native-dev, handystats, cocaine-runtime
Section: libs
Homepage: http://www.corp.com

Package: libcocaine-plugin-pgconnector3
Architecture: amd64
#Depends: cocaine-runtime, libcocaine-core2, handystats, 
#           libc6, libpq5, libboost-system1.55.0, libev4, libstdc++6, libgcc1
Depends: ${shlibs:Depends}, ${misc:Depends}
Section: libs
Priority: optional
Description: PgConnector plugin for Cocaine framework

Package: libcocaine-plugin-pgconnector3-dbg
Architecture: amd64
Section: debug
Priority: extra
Depends: ${shlibs:Depends}, ${misc:Depends}, libcocaine-plugin-pgconnector3 (= ${binary:Version})
Description: PgConnector plugin debug files

debian/libcocaine-plugin-pgconnector3.install

usr/lib/cocaine/pgconnector.cocaine-plugin
etc/cocaine/handystats.conf

debian/rules

#!/usr/bin/make -f
# See debhelper(7) (uncomment to enable)
# output every command that modifies files on the build system.
DH_VERBOSE = 1
export DH_OPTIONS=-v

DPKG_EXPORT_BUILDFLAGS = 1

include /usr/share/cdbs/1/class/cmake.mk
include /usr/share/cdbs/1/rules/debhelper.mk

DEB_DBG_PACKAGES := libcocaine-plugin-pgconnector3-dbg

install/libcocaine-plugin-pgconnector3::
        install -d $(DEB_DESTDIR)etc/cocaine
        install -m644 debian/handystats.conf $(DEB_DESTDIR)etc/cocaine/handystats.conf

What should I change in order to build packages properly with a customized filenames?